Six year results of the Rebalance mobile bearing total ankle replacement.

BACKGROUND: We report the outcomes of a prospective consecutive series of 267 total ankle replacements (TARs) using a new mobile bearing Rebalance® prosthesis. METHODS: Between April 2011 and December 2018, 267 consecutive Rebalance® prostheses were implanted in 255 patients at 3 different centers. Estimated survival curves with 95% confidence intervals were produced with the Kaplan-Meier method. 110 ankles were followed for at least 5 years and clinical and radiological outcomes were assessed in 92 of these ankles. RESULTS: Twenty-one ankles were revised at a mean of 34 (7-60) months. The estimated survival was 90% (95% CI 86-95) at 5 years and 88.3% (95% CI 83.-94 at 6 years. The ankles followed for at least 5 years demonstrated a median Likert score of 1 (1-4). Radiolucent zones were detected in 14% and osteolytic cysts in 3%. CONCLUSION: The survival rate of the Rebalance prosthesis conforms with other reports of similar designs. The satisfaction rate was high. Radiological zones and osteolytic cysts were found at a lower rate than usually reported for mobile bearing TARs. These results favour further use of this implant.

The change of first metatarsal head articular surface position after Lapidus arthrodesis.

BACKGROUND: The Lapidus procedure has been used for hallux valgus deformity correction since 1931. In some cases, the arthrodesis results in an unfavourable lateral inclination of first metatarsal head articular surface. The objective of our study was to evaluate the change of orientation of this articular surface in relation to the second metatarsal axis by comparing pre- and postoperative radiographs. The secondary target was to evaluate possible benefits of combination of Lapidus and Akin procedures in the reduction of hallux valgus deformity. METHODS: We evaluated 449 pre- and postoperative radiographs of 134 operations from 2010 to 2015. Routinely used angle measurements were performed on all X-rays. A sum of tangential angle to the second axis and distal articular set angle values was chosen as the best indicator for the deformity correction success. RESULTS: The mean value of these angles total was 5.2° ±9.3° before and 14.2° ±7.8° after the operation. In the group of patients, where the additional Akin osteotomy was used, the mean value was 5.3° ±8.4° before and 6.9° ±10.2° after the surgery. The mean difference in values between the two groups (with and without Akin procedure) was 7.3° of extra correction in favour of the group with the Akin osteotomy. CONCLUSIONS: The mean worsening of the tangential angle after Lapidus operation was 6.1° ±6.9°, which counts for significant deterioration after a surgery. The Akin osteotomy was found to be a valuable addition to the Lapidus arthrodesis, which improves the position of articular surfaces in first metatarsophalangeal joint.

Lateral release in hallux valgus deformity: from anatomic study to surgical tip.

The important part of hallux valgus deformity operations, especially in the case of an incongruent joint, is the release of the soft tissue on the lateral side of the first metatarsophalangeal joint. The purpose of the present anatomic study was, with preparation of the lateral structures of the joint and lateral conjoined tendon, to provide a background for a surgical tip of the release of the joint for an additional metatarsal osteotomy. For the present study, we used 30 specimens (15 left and 15 right) from 19 cadavers at the Institute of Anatomy, First Faculty of Medicine, Charles Faculty (Prague, Czech Republic). Only specimens that met the criteria of hallux valgus were included in the present study. The technique was based on the incision of the lateral sesamoid ligament and partial tenotomy of the lateral conjoined tendon from the first interdigital web space. The release was done gradually with supination and abduction of the big toe to achieve the smallest size of the tenotomy. The median of the tenotomy size of the conjoined tendon was 6.5 (range 5 to 14) mm. The median size of the conjoined tendon in the frontal plane just ventral to the sesamoid bone was 10.6 (range 8 to 14) mm. The technique of the release, in which the big toe was abducted and supinated, can minimize the size of the lateral conjoined tendon release and can minimize the possibility of a postoperative deformity.

Hypermobility of the first metatarsal bone in patients with rheumatoid arthritis treated by Lapidus procedure.

BACKGROUND: Foot deformities and related problems of the forefoot are very common in patients with rheumatoid arthritis. The laxity of the medial cuneometatarsal joint and its synovitis are important factors in the development of forefoot deformity. The impaired joint causes the first metatarsal bone to become unstable in the frontal and sagittal planes. In this retrospective study we evaluated data of patients with rheumatoid arthritis who underwent Lapidus procedure. We evaluated the role of the instability in a group of patients, focusing mainly on the clinical symptoms and X-ray signs of the instability. METHODS: The study group included 125 patients with rheumatoid arthritis. The indications of the Lapidus procedure were a hallux valgus deformity greater than 15 degrees and varus deformity of the first metatarsal bone with the intermetatarsal angle greater than 15 degrees on anterio-posterior weight-bearing X-ray. RESULTS: Data of 143 Lapidus procedures of 125 patients with rheumatoid arthritis, who underwent surgery between 2004 and 2010 was evaluated. Signs and symptoms of the first metatarsal bone instability was found in 92 feet (64.3%) in our group. The AOFAS score was 48.6 before and 87.6 six months after the foot reconstruction. Nonunion of the medial cuneometatarsal joint arthrodesis on X-rays occurred in seven feet (4.9%). CONCLUSION: The Lapidus procedure provides the possibility to correct the first metatarsal bone varus position and its instability, as well as providing the possibility to achieve a painless foot for walking. We recommend using the procedure as a preventive surgery in poorly symptomatic patients with rheumatoid arthritis in case of the first metatarsal bone hypermobility.

Ankle block implemented through two skin punctures.

BACKGROUND: Recently, peripheral nerve blocks have increasingly been used in orthopedic surgery. The foot block is an alternative for anesthesia in cases of forefoot and midfoot operations. We propose a modification of the block technique due to potential difficulties concerning the tibial nerve. MATERIALS AND METHODS: The spatial position of the tibial nerve in the neurovascular bundle, proximal to entering the tarsal tunnel and sural nerve behind lateral malleolus was measured on 60 dissected preparations. Modification of the block technique was proposed. A tibial nerve block was administered by inserting a needle, at an area above the upper edge of the heel bone, tangential to the Achilles tendon. The needle was then withdrawn and redirected to the frontal plane and inserted through the tissue, anterior to the Achilles tendon and laterally behind the lateral malleolus to block the sural nerve. A block of the saphenous nerve superficial and deep peroneal nerves was implemented by needle insertion subcutaneously two centimeters proximal to the crest of the ankle joint. The technique was then evaluated in the clinical part of the study in 84 operative procedures. RESULTS: The tibial nerve is located 21.1 mm +/- 2.1 mm from the medial aspect of the Achilles tendon and 11.6 mm +/- 1.3 mm deep in the neurovascular bundle. The distance from the posterior margin of the lateral malleolus to the sural nerve is 18.3 mm +/- 1.9 mm. We achieved a 93% success rate in implementation of the complete foot block in 84 operations. CONCLUSION: The technique, proposed in the anatomical portion of the study and evaluated in the clinical part, had a similar success rate when compared to techniques published in the literature. Though comparable to currently used techniques, this technique provides easier positioning of a patient and a complete block of the foot can be done with two skin injection sites.

Isolated talonavicular arthrodesis in patients with rheumatoid arthritis of the foot and tibialis posterior tendon dysfunction.

BACKGROUND: The foot is often affected in patients with rheumatoid arthritis. Subtalar joints are involved more frequently than ankle joints. Deformities of subtalar joints often lead to painful flatfoot and valgus deformity of the heel. Major contributors to the early development of foot deformities include talonavicular joint destruction and tibialis posterior tendon dysfunction, mainly due to its rupture. METHODS: Between 2002 and 2005 we performed isolated talonavicular arthrodesis in 26 patients; twenty women and six men. Tibialis posterior tendon dysfunction was diagnosed preoperatively by physical examination and by MRI. Talonavicular fusion was achieved via screws in eight patients, memory staples in twelve patients and a combination of screws and memory staples in six cases. The average duration of immobilization after the surgery was four weeks, followed by rehabilitation. Full weight bearing was allowed two to three months after surgery. RESULTS: The mean age of the group at the time of the surgery was 43.6 years. MRI examination revealed a torn tendon in nine cases with no significant destruction of the talonavicular joint seen on X-rays. Mean of postoperative followup was 4.5 years (3 to 7 years). The mean of AOFAS Hindfoot score improved from 48.2 preoperatively to 88.6 points at the last postoperative followup. Eighteen patients had excellent results (none, mild occasional pain), six patients had moderate pain of the foot and two patients had severe pain in evaluation with the score. Complications included superficial wound infections in two patients and a nonunion developed in one case. CONCLUSIONS: Early isolated talonavicular arthrodesis provides excellent pain relief and prevents further progression of the foot deformities in patients with rheumatoid arthritis and tibialis posterior tendon dysfunction.

Attachments of muscles as landmarks for implantation of shoulder hemiarthoplasty in fractures.

BACKGROUND: The attachments of muscles and the position of the humeral head are important for a good functional outcome of shoulder hemiarthroplasties after displaced fractures of the proximal humerus. Deviations in the attachments and changes in their spatial position with respect to the humeral head during surgical reconstruction change the biomechanics and reduce the range of motion of the should joint postoperatively. METHODS AND RESULTS: We used 198 humerus preparations and using 3-dimensional analysis measured the angular relationships between the humeral head axis and medial margin of the greater tuberosity (11.9 degrees +/- 9.1 degrees ), lateral margin of the lesser tuberosity (48.0 degrees +/- 7.8 degrees ), and the crest of the greater tuberosity (27.1 degrees +/- 9.6 degrees ). CONCLUSION: This study provides average values of the positions of the greater and lesser tuberosities with respect to the humeral head axis. We show that the greater and lesser tuberosities are more reliable than the transepicondylar line for reconstruction of humeral head retroversion. LEVEL OF EVIDENCE: Basic Science.