Hans-Jörg Trnka

Isolated Subtalar Arthrodesis

Background: The purposes of this retrospective study were to review the results of isolated subtalar arthrodesis in adults and to identify factors influencing the union rate. The hypotheses were that (1) the overall outcome is acceptable but is not as favorable as previously reported, (2) complication rates, especially the nonunion rate, are higher than previously reported, and (3) factors contributing to a less favorable union rate can be identified. Methods: Between January 1988 and July 1995, 184 consecutive isolated subtalar arthrodeses were performed in 174 adults (115 men and fifty-nine women) whose average age was forty-three years (range, eighteen to seventy-nine years). Eighty patients (46 percent) were smokers. The indications for the procedure included posttraumatic arthritis after a fracture of the calcaneus (109 feet), a fracture of the talus (thirteen feet), or a subtalar dislocation (thirteen feet); primary subtalar arthritis (thirteen feet); failure of a previous subtalar arthrodesis (twenty-eight feet); and residual congenital deformity (eight feet). Rigid internal fixation with one or two screws was used for all feet. Bone graft was used in 145 feet; the types of graft material included cancellous autograft (ninety-four feet), structural autograft (twenty-nine feet), cancellous allograft (seventeen feet), and structural allograft (five feet). Bone graft was not used in the remaining thirty-nine feet. Results: Clinical and radiographic follow-up examinations were performed for 148 (80 percent) of the 184 feet at an average of fifty-one months (range, twenty-four to 130 months) postoperatively. The average ankle-hindfoot score according to the modified scale of the American Orthopaedic Foot and Ankle Society (maximum possible score, 94 points) improved from 24 points preoperatively to 70 points at follow-up. Thirty feet had clinical evidence of nonunion. The union rate was 84 percent (154 of 184) overall, 86 percent (134 of 156) after primary arthrodesis, and 71 percent (twenty of twenty-eight) after revision arthrodesis. The union rate was 92 percent (ninety-three of 101 feet) for nonsmokers and 73 percent (sixty-one of eighty-three feet) for smokers (p < 0.05). Intraoperative inspection revealed that 42 percent (seventy-eight) of the 184 feet had evidence of more than two millimeters of avascular bone at the subtalar joint; all thirty nonunions occurred in this group (p < 0.05). A nonunion occurred in three of the five feet that had been treated with structural allograft and in two of the six feet in which the subtalar arthrodesis had been performed adjacent to the site of a previous ankle arthrodesis. After elimination of the subgroups of feet in patients who smoked, those that had had a failure of a previous subtalar arthrodesis, those that had been treated with a structural graft, and those that had had the subtalar arthrodesis adjacent to the site of a previous ankle arthrodesis, the union rate improved to 96 percent (seventy-three of seventy-six). Complications other than nonunion included prominent hardware requiring screw removal (thirty-six of 184 feet; 20 percent), lateral impingement (fifteen of 148 feet; 10 percent), symptomatic valgus malalignment (five of 148 feet; 3 percent), symptomatic varus malalignment (four of 148 feet; 3 percent), and infection (five of 184 feet; 3 percent). Conclusions: To the best of our knowledge, the present study includes the largest reported series of isolated subtalar arthrodeses in adults. Our results suggest that the outcome following isolated subtalar arthrodesis is not as favorable as has been reported in previous studies. The rate of union was significantly diminished by smoking, the presence of more than two millimeters of avascular bone at the arthrodesis site, and the failure of a previous subtalar arthrodesis (p < 0.05 for all). Other factors that probably affect the union rate include the use of structural allograft and performance of the arthrodesis adjacent to the site of a previous ankle arthrodesis.

The chevron osteotomy for correction of hallux valgus. Comparison of findings after two and five years of follow-up.

AbstractBackground:The chevron osteotomy, an accepted method for the correction of mild and moderate hallux valgus, is generally advocated for patients younger than the age of fifty years. The purposes of this prospective study were to compare the short-term (two-year) and intermediate-term (five-ye

Comparison of the Results of the Weil and Helal Osteotomies for the Treatment of Metatarsalgia Secondary to Dislocation of the Lesser Metatarsophalangeal Joints

We retrospectively reviewed the outcome of 30 patients who were treated surgically for metatarsalgia resulting from dislocation of one or more lesser metatarsophalangeal (MTP) joints. We used two treatments, including an osteotomy of the metatarsal head (Weil osteotomy, N = 15) or an osteotomy of the metatarsal shaft (Helal osteotomy, N = 15). Before surgery, all patients had been treated with various nonoperative modalities for a minimum of 6 months. Between 1991 and 1993,15 consecutive patients underwent a Helal osteotomy (22 metatarsals), and 15 consecutive patients were subsequently treated between 1994 and 1995 with a Weil osteotomy (25 metatarsals). All patients were evaluated clinically and radiographically at a mean follow-up period of 22 months (range, 12–39 months), noting especially persistent subluxation or dislocation, recurrent metatarsalgia, and transfer lesions. Patients managed with a Weil osteotomy had significantly higher satisfaction (P = 0.049), lower incidence of recurrent metatarsalgia (0 vs 27%, P = 0.107), and fewer transfer lesions (0 vs 41%, P = <0.001) than those managed with a Helal osteotomy. Furthermore, those managed with the Weil procedure had a higher percentage of radiographic reduction and maintenance of the MTP joint dislocation (21 of 25, 84% vs 8 of 22,36% P = 0.002) than those managed with the Helal procedure. In the Weil group, there was also no malunion or pseudoarthrosis; in the Helal group there were five malunions and three pseudoarthroses. Although the follow-up period for the Weil osteotomy (15 months) was shorter than that for the Helal osteotomy (26 months), the former group had higher American Orthopaedic Foot and Ankle Society forefoot scores, which were significantly different from the results attained with the Helal osteotomy. A telephone update was performed on the Weil osteotomy group at an average of 27 months postsurgery, and no patient had experienced changes since the clinical follow-up. We concluded that the Weil procedure is a satisfactory method for correcting metatarsalgia caused by dislocation of the MTP joint and that, because of the high complication rate, the Helal osteotomy is not an acceptable procedure for correcting this condition.

Six first metatarsal shaft osteotomies: mechanical and immobilization comparisons.

Because malunion (usually with dorsal elevation of the first metatarsal) has been reported after the treatment of severe hallux valgus deformities by proximal osteotomies, the current study was designed to compare the sagittal stability of six different metatarsal shaft osteotomies: the proximal crescentic, proximal chevron, Mau, Scarf, Ludloff, and biplanar closing wedge osteotomies. A plate was used in the biplanar closing wedge osteotomy; all others used screws for fixation. Ten fresh-frozen, human anatomic lower extremity specimens were used for each osteotomy. Failure loads were measured as units of force (newtons) and converted to pressure (kilopascals). Then the F-Scan system, which uses a thin insole to measure plantar pressure, was used to evaluate the pressure under the first metatarsal of seven volunteers using four types of shoes. According to the results, in patients with normal bone stock who are compliant, any of the four shoe types tested may be used after a Ludloff, Scarf, biplanar wedge (plantar screw fixation), or Mau osteotomy, but the wedge-based shoe should be used after a proximal crescentic or chevron osteotomy or for patients with severe osteopenic bone.

The Weil osteotomy: A SEVEN-YEAR FOLLOW-UP

We prospectively evaluated the one- and seven-year results of the Weil osteotomy for the treatment of metatarsalgia with subluxed or dislocated metatarsophalangeal joints in 25 feet of 24 patients. Good to excellent results were achieved in 21 feet (84%) after one year and in 22 (88%) after seven years. The American Orthopaedic Foot and Ankle Society score significantly improved from 48 (SD 15) points before surgery to 75 (SD 24) at one year, and 83 (SD 18) at seven years. The procedure significantly reduced pain, diminished isolated plantar callus formation and increased the patients capacity for walking. Redislocation of the metatarsophalangeal joint was seen in two feet (8%) after one year and in three (12%) after seven years. Although floating toes and restricted movement of the metatarsophalangeal joint may occur, the Weil osteotomy is safe and effective.

Dorsiflexion contracture after the Weil osteotomy: results of cadaver study and three-dimensional analysis.

For metatarsalgia caused by a dislocated lesser metatarsophalangeal (MTP) joint and isolated over-long lesser metatarsals, surgical treatment options without sacrificing the joint are limited. Recently, the Weil osteotomy has been advocated for the treatment of this deformity. In our experience, preliminary results with this technique have revealed a high rate of dorsiflexion contracture of the MTP joints at follow-up. We performed a cadaver study and a three-dimensional analysis on sawbones to investigate this phenomenon. In the cadaveric portion of this study, the second MTP joints of two fresh-frozen cadavers were dissected; the entire ray, with the metatarsal shaft, MTP joint, toe, and plantar fascia, was removed en bloc. After gross anatomic structures were photographed, a Weil osteotomy was performed at 25 relative to the long axis of the metatarsal shaft. The positions of muscles°, ligaments, and tendons were noted and photographed before and after the osteotomy. In the sawbones portion of this study, a Weil osteotomy was performed at four different angles (25°, 30°, 35°, and 40°) relative to the long axis of the metatarsal. To ensure reproducibility, the sawbone models were fixed proximally to a vertical milling machine with the second metatarsals inclined 15° to simulate the anatomic position. After making the cut, the plantar fragment was translated along the dorsal fragment proximally for a distance of 5 mm. Before and after the osteotomy, selected x, y, and z coordinates were obtained using a Microscribe 3D digitizer. Data analysis was performed with Microsoft Excel, and ANOVA was used to determine significant differences (p <0.05) between the various osteotomies. Analysis of the cadaver dissection revealed that after the Weil osteotomy, the tendons of the interosseous muscles move dorsally with respect to the axis of the MTP joint due to the depression of the plantar fragment of the metatarsal. The loss of their flexion effect on the joint permits the pull of the extensor to dorsiflex the toe. The size of the depression for the various osteotomies averaged: 25° osteotomy, 3.03 mm (range, 1.8 to 3.8 mm); 30° osteotomy, 3.2 mm (range, 1.9 to 4.0 mm); 35° osteotomy, 3.5 mm (range, 1.7 to 5.7 mm); and 40° osteotomy, 4.2 mm (range, 2.8 to 6.4 mm). Amounts of shortening relative to the long axis of the metatarsal for the various osteotomies averaged: 25° osteotomy, 5.03 mm (range, 4.77 to 5.30 mm); 30° osteotomy, 4.59 mm (range, 3.47 to 5.19 mm); 35° osteotomy, 4.27 mm (range, 2.87 to 5.00 mm); and 40° osteotomy, 3.65 mm (range, 3.20 to 4.31 mm). According to our analysis, depression of the plantar fragment always occurs after a Weil osteotomy. This depression changes the center of rotation of the MTP joint, and the interosseous muscles then act more as dorsiflexors than as plantarfexors.

Proximal metatarsal osteotomies: a comparative geometric analysis conducted on sawbone models.

We evaluated the change in position of the first metatarsal head using a three-dimensional digitizer on sawbone models. Crescentic, closing wedge, oblique shaft (Ludloff 8° and 16°), reverse oblique shaft (Mau 8° and 16°), rotational “Z” (Scarf), and proximal chevron osteotomies were performed and secured using 3-mm screws. The 16° Ludloff provided the most lateral shift (9.5 mm) and angular correction (14.5°) but also produced the most elevation (1.4 mm) and shortening (2.9 mm). The 8° Ludloff provided lateral and angular corrections similar to those of the crescentic and closing wedge osteotomies with less elevation and shortening. Because the displacement osteotomies (Scarf, proximal chevron) provided less angular correction, the same lateral displacement, and less shortening than the basilar angular osteotomies, based upon this model they can be more reliably used for a patient with a mild to moderate deformity, a short first metatarsal, or an intermediate deformity with a large distal metatarsal articular angle. These results can serve as recommendations for selecting the optimal osteotomy with which to correct a deformation.

The Weil osteotomy for treatment of dislocated lesser metatarsophalangeal joints: Good outcome in 21 patients with 42 osteotomies

Hardly any surgical methods are available for metatarsalgia caused by a dislocated lesser metatarsophalangeal joint (MTP) that do not sacrifice the joint. We reviewed retrospectively the outcome of 60 metatarsal Weil osteotomies for correction of dislocated lesser MTP joints in 31 patients. Between 1995 and 1996, 31 consecutive patients were treated with a Weil osteotomy at 2 institutions. The Weil osteotomy is an oblique osteotomy of the metatarsal neck and shaft, parallel to the ground surface, that controls shortening of the metatarsal by internal fixation with screws or pins. At an average final follow-up of 30 (24-44) months, all patients were interviewed, using a standardized questionnaire based on the AOFAS Lesser Metatarsophalangeal-Interphalangeal Scale. Recurrent or transfer metatarsalgia, formation of callus, mobility and dislocation of the MTP were noted on physical examination. Dorsoplantar and lateral weightbearing radiographs taken preoperatively and at the time of final follow-up were examined for alignment of the metatarsal heads, subluxation or dislocation and for evidence of nonunion, or malunion of the metatarsal osteotomy. We had excellent results in 21 patients (42 osteotomies). A major complication was plantar penetrating hardware in 10 cases (3 screws and 7 pins). We conclude that the Weil osteotomy is a good method for correcting metatarsalgia caused by dislocation of the MTP joint.

Moderate to severe hallux valgus deformity: correction with proximal crescentic osteotomy and distal soft-tissue release

Abstract Between 1991 and 1995, 96 patients (114 feet) were treated with a proximal crescentic metatarsal osteotomy and distal soft-tissue procedure for moderate to severe hallux valgus deformity [intermetatarsal (IM) angle > 15°, or hallux valgus (HV) angle > 30°]. At an average follow-up of 26 months, 8 men and 62 women (86 feet) with a mean age of 53.2 years were retrospectively reviewed. The HV angle averaged 41.1° preoperatively and 14.6° postoperatively. The respective values for the IM angle were 17.8° and 7.8°. Neither the average metatarsal shortening of 3 mm nor the dorsal angulation at the osteotomy site seen in 9% of cases evidenced any clinical significance at follow-up. Patient satisfaction was excellent or good in 91%, and the mean Mayo Clinic Forefoot Score (total 75 points) improved from 37.2 to 61.1 points. Complications included 8 cases of hallux varus and 5 cases of hardware failure. Based on this first study exclusively focusing on moderate to severe hallux valgus deformity, we conclude that proximal first metatarsal osteotomy in combination with a lateral soft-tissue procedure is effective in correcting moderate to severe symptomatic hallux valgus deformity with metatarsus primus varus (IM angle > 15° or HV angle > 30 °).

Intermediate-term Results of the Ludloff Osteotomy in One Hundred and Eleven Feet

BACKGROUND The modified Ludloff proximal first metatarsal osteotomy is indicated for the surgical correction of moderate-to-severe hallux valgus deformity associated with metatarsus primus varus. We report the intermediate-term results of this procedure. METHODS Ninety-nine patients (111 feet) with a mean age of fifty-six years underwent a modified Ludloff proximal first metatarsal osteotomy and a distal soft-tissue procedure at two institutions for the treatment of a moderate-to-severe hallux valgus deformity. The American Orthopaedic Foot and Ankle Society score and weight-bearing radiographs of the foot were assessed preoperatively and after a mean duration of follow-up of thirty-four months. Clinical and radiographic outcome was also compared between younger and older patients, with the arbitrarily chosen age of sixty years dividing the two groups. RESULTS The mean American Orthopaedic Foot and Ankle Society score improved significantly (p < 0.0001) from 53 points preoperatively to 88 points at the time of the most recent follow-up. The mean American Orthopaedic Foot and Ankle Society score for patients who were sixty years of age or less was significantly higher than that for patients who were more than sixty years of age (91 compared with 83 points; p = 0.0057). The mean hallux valgus angle decreased significantly from 35 degrees preoperatively to 9 degrees at the time of the most recent follow-up (p < 0.0001), and the mean intermetatarsal angle decreased significantly from 17 degrees to 8 degrees (p < 0.0001). All osteotomy sites united without dorsiflexion malunion but with a mean first metatarsal shortening of 2.2 mm. CONCLUSIONS To our knowledge, the present report describes the largest cohort of patients undergoing a modified Ludloff osteotomy for the correction of hallux valgus deformity that has been reported in the literature. Our intermediate-term results demonstrate that the procedure achieves significant correction of moderate-to-severe hallux valgus deformity, significant reduction in forefoot pain, and significant improvement in functional outcome. Patients with an age of sixty years or less appear to have a more favorable outcome.