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BACKGROUND: Short stems were introduced into total hip arthroplasty (THA) to preserve bone stock, to transmit more load to the proximal femur, and to enable minimal invasive approaches. This study is the first long-term study (with a follow-up of 10 years) of the survival as well as the clinical and radiographic outcomes of the Fitmore hip stem, a short curved uncemented stem. METHODS: In total, 123 Fitmore hip stems were prospectively evaluated. At the final 10-year follow-up, 80 Fitmore stems (78 patients: 30 female, 48 male) were eligible for evaluation. Clinical parameters were thigh pain, EQ-5D, Harris Hip Score (HHS) and Oxford Hip Score. Radiographic parameters were cortical hypertrophy (CH), bone condensation, cortical thinning, radiolucency, reactive lines, calcar rounding, calcar resorption, subsidence and varus/valgus position. RESULTS: After 10 years, there was a survival rate of 99% (1 revision because of aseptic stem loosening). HHS had improved from 59 to 94 and Oxford Hip Score from 22 to 43. CH rate after 1 year was 69% and after 10 years 74%. In the first year, radiolucency was found in 58% and in 17.5% after 10 years. Subsidence after 1 year was 1.6 ± 1.6 mm and 5.0 ± 3.1 mm after 10 years. CONCLUSIONS: The Fitmore hip stem showed a survival rate of 99% as well as good clinical and radiographic outcomes in the long-term follow-up of 10 years.

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Objectives: The literature on humeral torsion angles (retrotorsion) reveals great inconsistencies between methodology and values. Decreased retrotorsion was suspected to correlate with instability, but evidence is contradictory. The measurement according to the gold standard method of Bernageau and Godefroy (B&G) can be challenging especially in the presence of Hill-Sachs-lesions. Therefore, we have developed and evaluated a new measurement method for the humeral torsion angle on MRI-scans. Materials and Methods: Three investigators have measured 67 patients (35 with shoulder instability, 32 healthy) on axial MRIs with 603 measurements used for reliability calculation. The new Circle-method determines the retrotorsion by overlaying two circles on the transversal section of the humeral head. The first circle is adjusted congruent with the margin of the humeral head, whereas the second circle is adjusted to the greater tubercle. The line bisecting the centres of these circles is defined as the humeral head axis. This method was compared to B&G. Results: The mean retrotorsion angle of all patients was 25°± 25° (mean ± SD) with B&G, and 24° ± 27° with the Circle-method. Neither method revealed a significant difference between stable and unstable shoulders (p = 0.47). Of the 35 patients with unstable shoulders 21 (60%) presented Hill-Sachs lesions. No significant differences between patients with or without Hill-Sachs lesions (Circle-method: p = 0.61; B&G: p = 0.67). The reliability parameters for both methods were similar. Conclusions: The new Circle-method is as precise as the method of B&G. It may yield more consistent values in cases with substantial Hill-Sachs-lesions. Our data do not suggest retrotorsion as a predictor of instability.

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BACKGROUND: Asymptomatic acromioclavicular osteoarthritis (AC-OA) is a frequent finding in shoulder magnetic resonance imaging (MRI). Its natural course is unknown. Therefore, the question arises whether a resection should be performed simultaneously with shoulder surgery for another reason to prevent future pain and reoperation. The purpose of this study was to investigate the mid-term course of asymptomatic AC-OA. METHODS: Overall, 114 asymptomatic AC-OA diagnosed on MRI were followed for 7 years between 2011 and 2018. At baseline, MRI signal enhancement in the clavicle and acromion, OA grade, physical demand as well as the parameters (1) Constant Score Visual Analogue Scale, (2) pain on AC-joint compression, and (3) cross-body adduction test were measured. All patients were followed up after 7 years by interview, and in case of symptoms by clinical examination. The endpoint "deterioration" was reached if 2 of the 3 parameters turned worse. RESULTS: Asymptomatic AC-OA remained asymptomatic in 83% of cases, 7% turned better, 10% turned worse. Physical demand and osteoarthritis grade increased the risk of deterioration, whereas MRI signal enhancement in the clavicle or acromion had no influence on outcome. During follow-up, the frequency of pain on AC-joint compression increased from 11% to 16% (P = .24), the frequency of a positive cross-body adduction test increased from 6% to 20% (P = .017), and the mean Constant Score Visual Analogue Scale increased from 10 to 13 points (P < .001) indicating less pain. CONCLUSIONS: Asymptomatic AC-OA remained asymptomatic in 90% over 7 years. A simultaneous resection of an asymptomatic AC-OA during shoulder surgery for another reason is not indicated in every patient.

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BACKGROUND: An increased occurrence of cortical hypertrophy (CH) was observed 1-2 years after implanting short curved Fitmore hip stems. There are no published data about either the clinical relevance or the progression of CH over the long term. METHODS: Ninety-six primary total hip arthroplasties were performed between 2008 and 2010 using the Fitmore hip stem. Clinical and radiological parameters were recorded preoperatively and at 1, 2, 3, and 5 year follow-up. RESULTS: CH appeared mainly on antero-posterior radiographs in Gruen Zones 2, 3, 5, and 6. After 1 year, the diameter was 10 ± 2 mm and remained constant thereafter. The CH rate after 1 year was 69% and after 5 years 71%. Subsidence after 1 year was 1.6 ± 1.55 mm and 1.93 ± 1.72 mm after 5 years. Cortical thinning was 46% after 1 year and 56% after 5 years, mainly in Gruen Zones 7 and 8. In the first year radiolucencies were found in 51% in all Gruen Zones, and in 20% after 5 years. Patient, implant, and surgical factors did not correlate with radiological outcomes except that larger stems had more CH. After 5 years, the Harris Hip Score had improved from 59 to 94 and the Oxford Hip Score from 22 to 41. Radiographic parameters, notably CH, were not associated with clinical outcomes except that cortical thinning correlated with lower outcome scores. CONCLUSIONS: CH correlated neither with clinical outcome nor with patient, surgical or implant factors, except for a positive correlation with stem size. The Fitmore hip stems settled within the first year to a stable fixation and then remained almost unchanged. However, cortical thinning is common in Gruen Zone 7 and 8 meaning that there is stress-shielding.

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BACKGROUND: Stiffness after open hallux valgus surgery affects 7% to 38% of patients. Minimally invasive surgery (MIS) is thought to decrease this rate by reducing soft tissue trauma. MIS, now in its third generation, is advertised as delivering results superior to open surgery. However, no studies have reported stiffness or range of motion (ROM). METHODS: Between January 2014 and December 2015, a total of 50 patients received open scarf-Akin surgery and 48 received minimally invasive Chevron Akin (MICA) surgery. The endpoints were American Orthopaedic Foot & Ankle Society (AOFAS) score, range of motion, visual analog scale for pain, scar length, and subjective foot value. The minimal follow-up time was 2 years. RESULTS: Moderate stiffness occurred in 3 cases in both groups. In MICA, extension increased by 10 degrees while it remained unchanged in scarf. Both groups showed similar improvements in AOFAS score, pain, and subjective foot value. Radiographic evidence of correction was comparable, except for an increased shortening of the first metatarsal by 3 mm in MICA. The scars were smaller in MICA (1.2 cm) than in scarf (5 cm). Wound problems included delayed healing in 10% in scarf and wound infections in 4% in MICA. The rate of recurrence and other complications were comparable, except for reoperations, which were higher in MICA (27% mainly for protruding screws) than in scarf (8% mainly for stiffness). In MICA, 14% were intraoperatively converted to open surgery. CONCLUSION: MICA showed no advantages over scarf other than a shorter scar. The observed gain in extension could be related to the increased shortening of the first metatarsal because of the size of the burr. LEVEL OF EVIDENCE: Level II, prospective cohort (nonrandomized, comparative) study.

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OBJECTIVE: To compare the hindfoot alignment measured on standing HAV radiographs (Saltzman view) and on non-weight-bearing coronal MR images. MATERIALS AND METHODS: The apparent moment arm was measured on weight-bearing conventional radiographs (Saltzman views) and on MRIs of the ankle in 50 consecutive patients (mean age, 54 years; age range, 18-77 years). The evaluation was performed independently by three readers using analogous reference points for both methods. Positive values were assigned when the deepest point of the calcaneus was lateral to the tibial axis as valgus, negative values as varus. The intertechnique agreement and correlation for the measurements performed with HAV radiographs and MRI were assessed for each reader using the Bland-Altman method and the Pearson correlation coefficient, respectively. The interobserver agreement was assessed using the intraclass correlation coefficient. RESULTS: The means of apparent moment arms, with the standard deviation (SD) in parentheses, of three readers were +2.0 (±8.4) mm, +1.5 (±6.6) mm and -1.4 (±8.2) mm on HAV radiographs and +4.6 (±7.4) mm, +6.3 (±5.3) mm and +5.4 (±6.4) mm on MRI. The Bland-Altman analysis found a systematic bias for all three readers, corresponding to an overestimation of measurements with MRI (systematic bias ranging from 2.6 to 4.8 mm). The intertechnique correlation was found moderate to high. The Pearson coefficients for the three readers were 0.75, 0.64 and 0.65. The interobserver agreement among the three readers was 0.72, 0.77 and 0.68 for HAV, MRI and both modalities together, respectively. CONCLUSION: Hindfoot alignment can be estimated on MRI but the correlation between the values on HAV radiographs and MR images is only moderate with a tendency to increased positive values (valgization) on MR images.

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PURPOSE: The purpose of this study was to evaluate survival and clinical outcome of the Scandinavian total ankle replacement (STAR) prosthesis after a minimum of ten years up to a maximum of 19 years. METHODS: Fifty STAR prostheses in 46 patients with end stage ankle osteoarthritis operated between 1996 and 2006 by the same surgeon (MH) were included. Minimal follow-up was ten years (median 14.6 years, 95% confidence interval [CI] 12.9-16.4). Clinical (Kofoed score) and radiological assessments were taken before the operation and at one, ten (+2), and 16 (±3) years after implantation. The primary endpoint was defined as exchange of the whole prosthesis or conversion to arthrodesis (def. 1), exchange of at least one metallic component (def. 2), or exchange of any component including the inlay (due to breakage or wear) (def. 3). Survival was estimated according to Kaplan-Meier. Further reoperations related to STAR were also recorded. RESULTS: The ten year survival rate was (def. 1) 94% (CI 82-98%), (def. 2) 90% (CI, 77-96%), and (def. 3) 78% (CI 64-87%). The 19-year survival rate was (def. 1) 91% (CI 78-97%), (def. 2) 75% (CI 53-88%), and (def. 3) 55% (CI 34-71%). Considering any re-operations related to STAR, 52% (26/50) of prostheses were affected by re-operations. Mean pre-operative Kofoed score was 49, which improved to 84 after one year (n = 50), to 90 after ten years (n = 46), and to 89 after 16 years (n = 28). CONCLUSIONS: The survival rate for def. 1 and 2 was high. However, re-operations occurred in 52% of all STAR prosthesis. STUDY DESIGN: Retrospective cohort study, evidence Level 4.

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INTRODUCTION: The resection of os trigonum or posterior talar process as treatment for posterior ankle impingement is an established operation. However, the authors encountered several painful stress reactions in the posterior subtalar joint during follow-up resulting in persisting incapacity to do sports. METHODS: From March 2011 to July 2015, 29 patients with 30 feet were operated (22 endoscopic, 8 open resections). Average follow-up time was 43 ± 13 months. Complications were grouped into "none", "temporary disadvantage" and "permanent damage". The following radiographic parameters were measured: (1) length of posterior talar process or os trigonum, (2) length of the uncovered calcaneal joint surface after resection, (3) amount of resection. RESULTS: The rate of permanent damage was 13.3% (4 of 30 feet), and all four of these patients developed a painful stress reaction in the posterior subtalar joint. One temporary disadvantage (persistent pain for three months) was found. All patients with major complications showed retrospectively what we call the "risk configuration" -the radius of the talus ending within the subtalar joint. The length of the uncovered calcaneal joint surface was therefore significantly larger (6.4 mm ± 3.33) in feet with permanent damage than in feet without (1.06 mm ± 2.15, P < 0.001). CONCLUSION: The resection of os trigonum or posterior talar process has a complication rate of 13.3% with persisting inability to do sports due to painful stress reaction in the posterior subtalar joint. The only risk factor found was the "risk configuration". In such cases, the resection has to be made not anterior into the subtalar joint and patients have to be informed about this possible complication. STUDY DESIGN: Retrospective case series; Evidence Level 4.

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BACKGROUND: Depending on the direction of the subtalar joint, a foot deformity generally tends towards pronation (pes planovalgus) or supination (pes cavovarus). However, the combination of hindfoot varus and flat midfoot/forefoot (pes planovarus) is an exception to this rule. Pes planovarus has so far only been referred to in connection with Müller-Weiss disease and congenital disease. We diagnosed pes planovarus in otherwise healthy patients without these diseases. METHODS: Forty patients with 54 symptomatic feet who were treated between August 2012 and July 2016 were included (mean age, 44.1 ± 15.7 years; 15 male/25 female). They were selected from 1064 consecutive cases (3.8%). Inclusion criteria were hindfoot varus and flat midfoot/forefoot. Their symptoms, radiographs, and therapies within the first 3 months were retrospectively analyzed. The position in the hindfoot alignment view (HAV), talometatarsal-1 angle lateral (TMT1lat) and dorsoplantar (TMT1dp), talocalcaneal angle lateral (TCAlat) and dorsoplantar (TCAdp), and calcaneal pitch angle (CPA) were measured on a DICOM/PACS system. RESULTS: The mean radiological results (standard values from the literature in brackets) were as follows: the hindfoot was significantly in varus in the HAV (-6.9 ± 3.6 mm [-1.6 ± 7.2 mm]; P < .001), the TMT1lat was significantly flatter (-6.7 ± 5.8 degrees [8.4 ± 5.9 degrees]; P < .001), the TMT1dp was significantly less in abduction (1.5 ± 7.9 degrees [7.7 ± 8.2 degrees]; P = .005), the TCAdp showed no difference (25.9 ± 7.9 degrees [24.1 ± 5.7 degrees]; P = .118), the TCAlat was significantly larger (47.5 ± 6.1 degrees [43.4 ± 7.1 degrees]; P < .001), and the CPA was significantly flatter (17.6 ± 3.9 degrees [24.5 ± 3.0 degrees]; P < .001). The most frequent symptoms were stress-induced foot pain (n = 33), hallux valgus (n = 20), chronic ankle instability (n = 17), metatarsalgia (n = 15), chronic midfoot pain (n = 13), heel pain (n = 12), and lesser toe deformities (n = 8). Thirty-one feet were treated conservatively and 23 operatively. CONCLUSION: This study showed the existence of pes planovarus without Müller-Weiss disease or congenital disease. This unusual foot form leads to difficulties if standard treatment strategies are applied, which raises the issue of the correct treatment for such patients. LEVEL OF EVIDENCE: Level IV, retrospective case series.

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BACKGROUND: In a previous study, intraoperative positioning of the hindfoot by visual means resulted in the wrong varus/valgus position by 8 degrees and a relatively large standard deviation of 8 degrees. Thus, new intraoperative means are needed to improve the precision of hindfoot surgery. We therefore sought a hindfoot alignment guide that would be as simple as the alignment guides used in total knee arthroplasty. METHODS: A novel hindfoot alignment guide (HA guide) has been developed that projects the mechanical axis from the tibia down to the heel. The HA guide enables the positioning of the hindfoot in the desired varus/valgus position and in plantigrade position in the lateral plane. The HA guide was used intraoperatively from May through November 2011 in 11 complex patients with simultaneous correction of the supramalleolar, tibiotalar, and inframalleolar alignment. Pre- and postoperative Saltzman views were taken and the position was measured. RESULTS: The HA guide significantly improved the intraoperative positioning compared with visual means: The accuracy with the HA guide was 4.5 ± 5.1 degrees (mean ± standard deviation) and without the HA guide 9.4 ± 5.5 degrees (P < .05). In 7 of 11 patients, the preoperative plan was changed because of the HA guide (2 avoided osteotomies, 5 additional osteotomies). CONCLUSIONS: The HA guide helped to position the hindfoot intraoperatively with greater precision than visual means. The HA guide was especially useful for multilevel corrections in which the need for and the amount of a simultaneous osteotomy had to be evaluated intraoperatively. LEVEL OF EVIDENCE: Level IV, case series.

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Charcot medial column and midfoot deformities are associated with rocker bottom foot, recurrent plantar ulceration, and consequent infection. The primary goal of surgical intervention is to realign and stabilize the plantar arch in a shoe-able, plantigrade alignment. Different fixation devices, including screws, plates, and external fixators, can be used to stabilize the Charcot foot; however, each of these methods has substantial disadvantages. To assess the effectiveness of rigid, minimally invasive fixation of the medial column and midfoot, 8 cases of solid intramedullary bolt fixation for symptomatic Charcot neuroarthropathy were reviewed. The patients included 6 males (75%) and 2 females (25%), with a mean age of 63 (range 46 to 80) years. The Charcot foot deformity was caused by diabetic neuropathy in 7 cases (87.5%) and alcoholic neuropathy in 1 (12.5%). The mean duration of postoperative follow-up period was 27 (range 12 to 44) months. The mean radiographic correction of the lateral talar-first metatarsal angle was 15° (range 3° to 19°), and the mean radiographic correction of the dorsal midfoot dislocation was 9 (range -4 to 23) mm. The mean loss of correction of the lateral talar-first metatarsal angle and midfoot dislocation after surgery was 7° (range 0° to 26°) and 1 (range 0 to 7) mm, respectively. No bolt breakage was observed, and no cases of recurrent or residual ulceration occurred during the observation period. Bolt removal was performed in 3 cases (37.5%), 2 (25%) because of axial migration of the bolt into the ankle joint and 1 (12.5%) because of infection. The results of the present review suggest that a solid intramedullary bolt provides reasonable fixation for realignment of the medial column in cases of Charcot neuroarthropathy.

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BACKGROUND: A large number of parameters are registered by pedobarography, usually requiring a research setting for interpretation. The purpose of this study was to evaluate which pedobarographic parameters (adjusted for walking speed and body weight) discriminate between healthy volunteers and patients after ankle or tibiotalocalcaneal arthrodesis. Furthermore, we evaluated which parameters are associated with the American Orthopaedic Foot and Ankle Society (AOFAS) score. METHODS: Thirty-five healthy volunteers, 57 patients with ankle and 42 with tibiotalocalcaneal arthrodesis were assessed by AOFAS scores and dynamic pedobarography. The arthrodesis patients were further investigated with radiographs. Median follow up was 4 years. Eighteen basic parameters were measured each in the hind-, mid-, and forefoot. For dimension reduction, we represented a pre-selected set of 9 parameters by two indices (load, rollover). We used ordinal logistic and multiple linear regression to address the questions. FINDINGS: The midfoot index of load was the most important pedobarographic predictor (interquartile range odds ratio 100; 95% confidence interval 13, 771) for belonging to the healthy volunteers rather than the ankle or tibiotalocalcaneal arthrodesis groups. Similarly, it was an independent predictor for the AOFAS score (interquartile range effect 5 points; 95% confidence interval 1, 9). Healthy volunteers had a deeper midfoot depression in the force/pressure time graphs compared to patients after arthrodesis. INTERPRETATION: When evaluating foot function after ankle or tibiotalocalcaneal arthrodesis, the interpretation of a large number of pedobarographic parameters can be reduced to the interpretation of the midfoot index of load and the evaluation of the force/pressure time graphs.

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BACKGROUND: We found treatment of clavicular midshaft fractures using titanium elastic nails (TENs) in combination with postoperative free ROM was associated with a complication rate of 78%. The use of end caps reduced the rate to 60%, which we still considered unacceptably high. Thus, we explored an alternative approach. QUESTIONS/PURPOSES: We investigated whether (1) the complication rate could be reduced by cautious lateral advancement of the TENs, intraoperative oblique radiographs to rule out lateral perforation, and limited ROM postoperatively; (2) fluoroscopy time could be reduced; and (3) shoulder function would be reasonable. PATIENTS AND METHODS: From March 2006 to December 2009, we treated 44 patients with midshaft clavicular fractures with TENs and end caps. In the first group (n = 15), the TEN was advanced laterally using an oscillating drill. The patients were permitted free ROM. In the second group (n = 29), the TEN was advanced by hand, conversion to open reduction followed two failed closed attempts and lateral perforation was checked with an intraoperative oblique radiograph. Furthermore, anteversion and abduction of the shoulder were limited to 90° for the first 6 weeks. Minimum followup was 12 months (mean, 16.7 months; range, 12-28 months). RESULTS: The total complication rate was reduced from nine of 15 in the first group to five of 29 in the second group. Medial perforations ceased with the use of the end cap. Fluoroscopy time was reduced from a mean of 10 to 4 minutes by converting to open reduction after two failed closed attempts. All but three patients exhibited full shoulder ROM at three months and these three had a slight deficit of 10° to 20° in anteversion and/or abduction. At last followup, the mean American Shoulder and Elbow Surgeons score was 92 (range, 88-100) and the Disability of the Arm, Shoulder, and Hand score 1.4 (range, 0-12.5). CONCLUSIONS: Cautious insertion of the TENs, intraoperative oblique radiographs, and limiting the ROM for 6 weeks postoperatively reduced the complication rate. Using TENs with end caps for midshaft clavicular fractures is minimally invasive while associated with comparable complication rates and function to plate osteosynthesis. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

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BACKGROUND: Alignment is instrumental for success and long-term survival of Total Ankle Replacement (TAR). At this point in TAR, only coronal alignment in the region of the tibiotalar joint or above has been assessed because inframalleolar deformity is difficult to visualize radiographically. The Hindfoot Alignment View (HAV) allows visualization of the hindfoot position relative to the tibia. The purpose of this study was to evaluate the clinical relevance of this view in assessing patients with TAR. MATERIALS AND METHODS: Twenty-eight consecutive patients with a Hintegra-TAR with an average followup of 4.1 ± 1.5 years were followed with (1) AOFAS and SF-36 scores, (2) visual judgment of the hindfoot position, (3) HAV and AP/lateral radiographs, (4) dynamic pedobarography (Novel emed m/E, Munich, Germany). RESULTS: The HAV position correlated well with different load parameters on heel strike (r = 0.44 to 0.62) but not with the varus-valgus load pattern of the rest of the foot. Visual judgment and TAR joint line did not correlate to radiographic hindfoot alignment or to pedobarographic load distribution. The hindfoot alignment measured by the HAV correlated significantly to the Physical Function and Role Physical of SF-36. No correlation was found to other SF36-qualities or the AOFAS-score. CONCLUSION: Inframalleolar alignment, as assessed by the HAV, influenced the dynamic pedobarographic load pattern and clinical outcome. Visual judgment and TAR joint line were not accurate enough to estimate the hindfoot alignment or dynamic load pattern. We believe adjusting the hindfoot correctly with HAV might improve long-term outcome and survival of TAR.

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BACKGROUND: The Saltzman-el-Khoury hindfoot alignment view (HAV) is considered the gold standard for assessing the axis from hindfoot to tibia. However, it is unclear whether radiographic alignment influences dynamic load distribution during gait. QUESTIONS/PURPOSES: We evaluated varus-valgus alignment by the HAV and its influence on dynamic load distribution in ankle and tibiotalocalcaneal (TTC) arthrodesis. PATIENTS AND METHODS: We clinically assessed 98 patients (ankle, 56; TTC, 42) with SF-36 and American Orthopaedic Foot and Ankle Society (AOFAS) scores, visual hindfoot alignment, HAV angle, and dynamic pedobarography using a five-step method. For comparison, 70 normal feet were evaluated. Minimum followup was 2 years (average, 4.11 years; range, 2-6 years). RESULTS: The mean HAV angle was -0.8° ± 7.8° for ankle and -1.2° ± 6.9° for TTC arthrodesis. The HAV angle correlated with pedobarographic load distribution (r = 0.35-0.53). Radiographic alignment did not influence SF-36 or AOFAS scores; however, load distribution correlated to qualities of these scores. Visual alignment only predicted the corresponding HAV angle in 48%. To reproduce the dynamic load of healthy subjects, HAV angles of 5° to 10° valgus were needed. CONCLUSIONS: Visual positioning is inadequate to determine intraoperative positioning and resulted in a varus position with a relatively large SD. The HAV should be used to assess the hindfoot alignment correctly. HAV angles of 5° to 10° valgus are needed to reproduce a physiologic gait pattern.

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UNLABELLED: A structural graft often is needed to fill gaps during reconstructive procedures of the ankle and hindfoot. Autograft, the current gold standard, is limited in availability and configuration and is associated with donor-site morbidity in as much as 48%, whereas the alternative allograft carries risks of disease transmission and collapse. Trabecular metal (tantalum), with a healing rate similar to that of autograft, high stability, and no donor-site morbidity, has been used in surgery of the hip, knee, and spine. However, its use has not been documented in foot and ankle surgery. We retrospectively reviewed nine patients with complex foot and ankle arthrodeses using a tantalum spacer. Minimum followup was 1.9 years (average, 2 years; range, 1.9-2.4 years). Bone ingrowth into the tantalum was analyzed with micro-CT in three of the nine patients. All arthrodeses were fused clinically and radiographically at the 1- and 2 year followups and no complications occurred. The American Orthopaedic Foot and Ankle Society score increased from 32 to 74. The micro-CT showed bony trabeculae growing onto the tantalum. Our data suggest tantalum may be used as a structural graft option for ankle and subtalar arthrodesis. All nine of our patients achieved fusion and had no complications. Using tantalum obviated the need for harvesting of the iliac spine. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

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BACKGROUND: Intramedullary nailing of clavicular midshaft fractures using the titanium elastic nail has been described as a technically easy, minimally invasive operation with few complications and an early return to competitive sports. HYPOTHESIS: The results reported thus far have been positive. The titanium elastic nail is associated with multiple intraoperative and postoperative problems. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: From April 2004 to March 2007, 34 patients at our institution were treated with intramedullary nailing. A standard titanium elastic nail was used in 19 cases and a titanium elastic nail with an end cap in 15 cases. The titanium elastic nail was inserted and advanced under fluoroscopic control. A short incision at the fracture site was made for open reduction if needed. Postoperatively, free range of motion was allowed. RESULTS: In 62% of patients, open reduction was necessary independent of fracture type, flattening of the titanium elastic nail, or transverse fragments. Operating time was 44 minutes (range, 10-105 minutes) and fluoroscopy time 9 minutes (range, 2-25 minutes). In 70% of patients, problems or complications occurred (7 medial perforations, 7 lateral penetrations, 1 titanium elastic nail breakage, 1 titanium elastic nail dislocation, 7 hardware irritations). The reoperation rate was 36%. Medial migration and pain were significantly reduced by using an end cap. CONCLUSION: Intramedullary nailing of clavicular midshaft fractures using the titanium elastic nail is a technically demanding operation with various complications in the postoperative phase. This study might explain why the implant has not yet achieved widespread application, despite the fact that other authors have reported good results. Amending the operative technique and postoperative treatment might improve the outcome in the future.

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Chronic ankle instability (CAI) is a frequent sport orthopaedic entity. Although many risk factors have been studied extensively, little is known how it is influenced by the osseous joint configuration. Based on lateral X-rays, the radius of the talar surface and the tibial coverage of the talus (sector alpha) were measured on a DICOM/PACS system in 52 patients with CAI and an age- and sex-matched control group. The talar radius was found to be larger in patients with CAI (21.2 +/- 2.4 mm) than in the control group (17.7 +/- 1.9 mm; P < 0.0001). The tibio-talar sector was smaller in patients with CAI (80 degrees +/- 5.1 degrees ) than in the control group (88.4 degrees +/- 7.2 degrees ; P < 0.0001). The aim of this study is to analyse the biomechanical influence of the clinical data on stability of the ankle joint. A two-dimensional model of the tibio-talar joint in the sagittal plane was developed. The joint configuration was described by the tibio-talar sector (alpha) and the radius (r) of the talus. The force (F = F (BW) tan alpha/2) and energy (E = F (BW) r [1 - cos alpha/2]) to dislocate the talus out of the tibial plafond were deduced. Ankle stability is a function of the tibio-talar sector: the force necessary to dislocate the joint is decreasing with a smaller sector. The clinical data show that the force needed to dislocate the ankle of CAI patients was 14% weaker than the one needed in the case of healthy subjects (P < 0.0001). The energy to dislocate the ankle depends both on the sector and the radius. The clinical data do not show a significant difference between the energy needed to dislocate the joint of CAI patients and the one of healthy subjects. This is because there is a correlation of a small sector and a large radius for CAI ankles. CAI is associated with an unstable osseous joint configuration, which is characterized by a larger radius of the talus and a smaller tibio-talar sector. The findings of the biomechanical model explain the clinical observations and demonstrate how stability of the ankle joint is influenced by the osseous configuration. Surgical ankle ligament stabilization might be more recommended in patients with an unstable osseous configuration as such patients have a disposition for recurrent sprains. Removing anterior osteophytes for anterior impingement should be done carefully in CAI patients because this would decrease the tibial coverage of the talus and thus dispose the talus to dislocate anteriorly. People who have an unstable ankle configuration and who nevertheless engage in activities with high risk of ankle sprains could be asked to wear ankle protecting sports equipment.

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