CT-based radiostereometric analysis for assessing midfoot kinematics: precision compared with marker-based radiostereometry.

BACKGROUND AND PURPOSE: 3-dimensional midfoot motion is hard to evaluate in clinical practice. We present a new computed tomography (CT)-based radiostereometric analysis (CT-RSA) technique to examine in vivo midfoot kinematics during single-leg stance and compare it with marker-based radiostereometry (RSA). PATIENTS AND METHODS: 8 patients were examined with bilateral non- and full-weight-bearing CT images of the midfoot. 1st tarsometatarsal motion was analyzed using a surface-registration technique (CT-RSA). As all patients had unilateral tantalum markers in the 1st cuneiform (C1) and 1st metatarsal (M1), comparison of precision with markerbased RSA was performed. CT-RSA precision was evaluated with surface registration of both C1-M1 bone and C1-M1 tantalum markers, while RSA precision was determined with C1-M1 markers only. Additionally, to remove motion bias, we evaluated intrasegmental CT-RSA precision by comparing proximal with distal part of M1. RESULTS: Under physical load, the primary movement for the 1st tarsometatarsal joint was M1 dorsiflexion (mean 1.4°), adduction (mean 1.4°), and dorsal translation (mean 1.1 mm). CT-RSA precision, using surface bone or markers, was in the range of 0.3-0.7 mm for translation and 0.6-1.6° for rotation. In comparison, RSA precision was in the range of 0.4-0.9 mm for translation and 1.0-1.7° for rotation. Finally, intrasegmental CT-RSA precision was in the range of 0.1-0.2 mm for translation and 0.4-0.5° for rotation. CONCLUSION: CT-RSA is a valid and precise, non-invasive method to measure midfoot kinematics when compared with conventional RSA.

[Lateral ankle ligament injuries]. / Laterale ankelligamentskader.

Lateral ankle ligament injuries occur in connection with inversion traumas and are one of the most common injuries, both in the general population and among athletes. A lateral ankle ligament injury weakens the stabilising structures in the ankle and disposes the ankle joint to prolonged instability. Acute lateral ankle ligament injuries with no suspicion of fracture can be treated and followed up conservatively in the primary health service. In this clinical review article, we emphasise the importance of adequate physical training before referral to an MRI and orthopaedic surgeon for further assessment. Patients with chronic instability who fail to respond to adequate conservative treatment should be referred for surgical assessment.

Does temporary bridge plate fixation preserve joint motion after an unstable Lisfranc injury?

BACKGROUND: Recently, temporary bridge plate fixation has gained popularity in the treatment of unstable Lisfranc injuries. The technique aims to reduce the risk of posttraumatic osteoarthritis, and after plate removal, the goal is to regain joint mobility. Here we explore marker-based radiostereometric analysis (RSA) to measure motion in the 1st tarsometatarsal (TMT) joint and asses the radiological outcome in patients treated with this surgical technique. METHOD: Ten patients with an unstable Lisfranc injury were included. All were treated with a dorsal bridge plate over the 1st TMT joint and primary arthrodesis of the 2nd and 3rd TMT joints. The plate was removed four months postoperatively. Non- and weight-bearing RSA images were obtained one and five years postinjury to assess joint mobility and signs of osteoarthritis. RESULTS: Detectable 1st TMT joint motion was observed in 2/10 patients after one year, and 6/9 patients after five years. At the final follow-up, mean 1st TMT dorsiflexion was 2.0°. Radiologically, the incidence of posttraumatic osteoarthritis was present in 4/10 patients after one year, and 5/9 patients after five years. All patients had observed TMT joint stability throughout the follow-up period. CONCLUSION: Preservation of joint motion can be achieved with a temporary bridge plate fixation over the 1st TMT joint. TYPE OF STUDY/LEVEL OF EVIDENCE: Prospective cohort study/Therapeutically level IV.

Arthroscopic Repair of Chronic Plantar Plate Tears of the First Metatarsophalangeal Joint: A New Surgical Technique With Patient Outcomes.

Background: Most plantar plate tears of the first metatarsophalangeal joint can be treated successfully by nonoperative means. Primary repair may be indicated to restore continuity of the plantar structures and joint stability. Inadequate or failed nonoperative treatment may cause persistent pain and disability and thereby represent a career-threatening injury to an athlete. The chronic plantar plate tears are difficult both to diagnose and to treat. When surgical treatment is indicated, traditionally a wide plantar or 2 parallel incisions are used. An arthroscopic approach allows for verification and visualization of the injury and, at the same time, repair of the injury. Purpose: To describe findings of plantar plate tears, present a new arthroscopic procedure for plantar plate tear repair, and present the outcomes after surgery. Study Design: Case series; Level of evidence, 4. Methods: This was a retrospective study on the first 10 patients treated with the arthroscopic technique. The patients underwent surgery between June 2017 and January 2021. Patient data, clinical symptoms and findings, and operative details were obtained from the patient records. Patients were contacted via email to complete patient-reported outcome measures (Manchester Oxford Foot Questionnaire [MOxFQ] and Numeric Rating Scale [NRS] for pain). Results: Four female and 6 male patients with a median age of 24 years (range, 12-44 years) were operated on at a median of 20 months (range, 2-38 months) after injury. Of the 10 patients, 8 had a hyperextension injury of the first metatarsophalangeal joint and 7 had a subtle valgus malalignment of the hallux; 8 patients were injured during sport activity. All patients reported plantar pain at pushoff. All but 1 patient returned to the same level of preinjury activity within 6 months. At a median of 29 months (range, 7-49 months) after surgery, the median MOxFQ score was 6 (range, 0-41) and the median NRS pain score was 0. Conclusion: Arthroscopic plantar plate repair of chronic plantar plate tears resulted in a high rate of return to activity/sport and excellent outcome scores.

Outcome after nonoperative treatment of stable Lisfranc injuries. A prospective cohort study.

BACKGROUND: The aim of this study was to evaluate the outcome after nondisplaced and stable Lisfranc injuries. METHODS: 26 patients with injuries to the Lisfranc joint complex detected on CT scans, but without displacement were tested to be stable using a fluoroscopic stress test. The patients were immobilized in a non-weightbearing short leg cast for 6 weeks. The final follow-up was 55 (IQR 53-60) months after injury. RESULTS: All the Lisfranc injuries were confirmed to be stable on follow-up weightbearing radiographs at a minimum of 3 months after injury. Median American Foot and Ankle Society (AOFAS) midfoot score at 1-year follow-up was 89 (IQR 84-97) and at final follow-up 100 (IQR 90-100); The AOFAS score continued to improve after 1-year (P=.005). The median visual analog scale (VAS) for pain was 0 (IQR 0-0) at the final follow-up. One patient had radiological signs of osteoarthritis at 1-year follow-up. CONCLUSION: Stable Lisfranc injuries treated nonoperatively had an excellent outcome in this study with a median follow-up of 55 months. The AOFAS score continued to improve after 1 year.

Unilateral, Volume-expanding Os Subcalcis: Patient History and Treatment: A Case Report.

Accessory bones of the foot are common, but the presence of accessory bones located at the plantar aspect of the calcaneus is rare. We present the case of a 72-year-old female that suffered with a volume expanding os subcalcis. Due to marked disability, the large os subcalcis was excised with a favorable outcome.

Temporary Bridge Plating vs Primary Arthrodesis of the First Tarsometatarsal Joint in Lisfranc Injuries: Randomized Controlled Trial.

BACKGROUND: Unstable Lisfranc injuries are best treated with anatomic reduction and stable fixation. There are controversies regarding which type of stabilization is best. In the present study, we compared primary arthrodesis of the first tarsometatarsal (TMT) joint to temporary bridge plating in unstable Lisfranc injuries. METHODS: Forty-eight patients with Lisfranc injuries were included and followed for 2 years. Twenty-four patients were randomized to primary arthrodesis (PA) of the medial 3 TMT joints, whereas 24 patients were randomized to temporary bridge plate (BP) over the first TMT joint and primary arthrodesis of the second and third TMT joints. The main outcome parameter was the American Orthopaedic Foot & Ankle Society (AOFAS) midfoot scale and the secondary outcome parameters were the 36-Item Short Form Health Survey (SF-36) and visual analog scale for pain (VAS pain). Computed tomography (CT) scans pre- and postoperatively were obtained. Radiographs were obtained at follow-ups. Pedobarographic examination was performed at the 2-year follow-up. Twenty-two of 24 patients in the PA and 23/24 in the BP group completed the 2-year follow-up. RESULTS: The mean AOFAS midfoot score 2 years postoperatively was 89 (SD 9) in the PA group and 85 (SD 15) in the BP group (P = .32). There were no significant differences between the groups with regard to SF-36 or VAS pain scores. The alignment of the first metatarsal was better in the BP group than in the PA group measured by the anteroposterior Meary angle (P = .04). The PA group had a reduced peak pressure under the fifth metatarsal (P = .047). In the BP group, 11/24 patients had radiologic signs of osteoarthritis in the first TMT joint. CONCLUSION: Both treatment groups had good outcome scores. The first metatarsal was better aligned in the BP group; however, there was a high incidence of radiographic osteoarthritis in this group. LEVEL OF EVIDENCE: Therapeutic level I, prospective randomized controlled study.

Results After Percutaneous and Arthroscopically Assisted Osteosynthesis of Calcaneal Fractures.

BACKGROUND: Operative treatment of calcaneal fractures using the extensile lateral approach is associated with high rates of soft tissue complications. In the past years, there has been a trend toward less invasive surgical approaches. Percutaneous and arthroscopically assisted calcaneal osteosynthesis (PACO) combines the advantages of visualization of the posterior facet of the subtalar joint with a minimally invasive approach. METHODS: We conducted a follow-up of 25 patients with 26 calcaneal fractures (Sanders II and III), treated with PACO with a minimum follow-up of 12 months. The median age was 44 years (range, 21-72) and the follow-up period 15 months (12-33). Our clinical outcomes were the Manchester-Oxford Foot Questionnaire (MOxFQ), the Calcaneus Fracture Scoring System (CFSS), the American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot score, the Short-Form-36 (SF-36), the visual analog scale (VAS) for pain, and the number of complications. Radiographs on follow-up were obtained to evaluate the reduction of the fractures as well as osteoarthritis of the subtalar joint. RESULTS: The median MOxFQ score was 26.6 (0-76.6), the CFSS score 85 (26-100), and the AOFAS score 85 (50-100). The VAS pain score was 0 (0-5.7) at rest and 4.1 (0-8.2) during activity. The Böhler angle improved from a mean (SD) of 3.5 (12.3) degrees preoperatively to 27.7 (10.5) degrees postoperatively. The follow-up radiographs showed subsidence of the fractures and a Böhler angle of 20.3 (12.9) degrees. There were no wound-healing complications. Two patients had additional surgery with screw removal due to prominent hardware. CONCLUSION: Our results suggest that PACO gives good clinical outcomes and a low risk of complications in selected calcaneal fractures. Prospective long-term studies will be necessary to better document the potential advantages and limitations of this operating technique. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Lisfranc injuries: Incidence, mechanisms of injury and predictors of instability.

BACKGROUND: In Lisfranc injuries the stability of the tarsometatarsal joints guides the treatment of the injury. Determining the stability, especially in the subtle Lisfranc injuries, can be challenging. The purpose of this study was to identify incidence, mechanisms of injury and predictors for instability in Lisfranc injuries. METHODS: Eighty-four Lisfranc injuries presenting at Oslo University Hospital between September 2014 and August 2015 were included. The diagnosis was based on radiologically verified injuries to the tarsometatarsal joints. Associations between radiographic findings and stability were examined. RESULTS: The incidence of Lisfranc injuries was 14/100,000 person-years, and only 31% were high-energy injuries. The incidence of unstable injuries was 6/100,000 person-years, and these were more common in women than men (P = 0.016). Intraarticular fractures in the two lateral tarsometatarsal joints increased the risk of instability (P = 0.007). The height of the second tarsometatarsal joint was less in the unstable injuries than in the stable injuries (P = 0.036). CONCLUSION: The incidence of Lisfranc injuries in the present study is higher than previously published. The most common mechanism of injury is low-energy trauma. Intraarticular fractures in the two lateral tarsometatarsal joints, female gender and shorter second tarsometatarsal joint height increase the risk of an unstable injury. LEVEL OF EVIDENCE: Level III, cross-sectional study.

Open Reduction and Internal Fixation of Acute Lisfranc Fracture-Dislocation with Use of Dorsal Bridging Plates.

Lisfranc injuries consist of a wide spectrum of injuries, ranging from subtle injuries to severe fracture-dislocations. Injuries with instability of the tarsometatarsal, intercuneiform, or naviculocuneiform joints should be treated with anatomic reduction and stable fixation. The best method of fixation is debated. Transarticular screw fixation has the disadvantage of damaging the tarsometatarsal joints. Bridging the tarsometatarsal joints with use of low-profile locking plates avoids the placement of screws through the joint and potentially reduces the risk of posttraumatic arthritis. Primary arthrodesis of the 3 medial tarsometatarsal joints is also an option in treating Lisfranc injuries and has been shown to lead to better outcomes compared with transarticular screw fixation in ligamentous Lisfranc injuries. In this article, we show the technique of open reduction and internal fixation of Lisfranc fracture-dislocation with use of dorsal bridging locking plates. The following steps are presented in the video: (1) incision technique with use of a dorsomedial incision and a dorsolateral incision, (2) open reduction and temporary fixation of the tarsometatarsal joints with use of Kirschner wires, (3) confirmation of anatomic reduction of the tarsometatarsal joints with direct visualization and fluoroscopy, (4) fixation of the medial 3 tarsometatarsal joints with dorsal bridging locking plates, (5) placement of a "homerun" screw from the medial cuneiform to the base of the second metatarsal, (6) fixation of the fourth and fifth tarsometatarsal joints with Kirschner wires, and (7) checking of reduction and fixation with use of fluoroscopy and performance of wound closure. Postoperatively, the foot is kept non-weight-bearing in a below-the-knee cast for 6 weeks, followed by 6 weeks of protected weight-bearing in a walker boot. Any Kirschner wires fixating the fourth and fifth tarsometatarsal joints are removed 6 weeks postoperatively. We prefer to remove the dorsal bridging plates 4 to 6 months postoperatively. Anatomic reduction and stable fixation is associated with better functional outcomes. Hardware failure and loss of reduction are potential complications that can lead to worse outcomes.

Tibial Nerve Palsy After Lateralizing Calcaneal Osteotomy.

Background: Lateralizing calcaneal osteotomy (LCO) is a common procedure used to correct hindfoot varus. Several complications have been described in the literature, but only a few articles describe tibial nerve palsy after this procedure. Our hypothesis was that tibial nerve palsy is a common complication after LCO. Methods: A retrospective study of patients undergoing LCO for hindfoot varus between 2007 and 2013 was performed. A total of 15 patients (18 feet) were included in the study. The patients were examined for tibial nerve deficit, and all the patients were examined with a computed tomography (CT) scan of both feet. Patients with a preexisting neurological disease were excluded. The primary outcome was tibial nerve palsy, and the secondary outcomes were reduction of the tarsal tunnel volume, the distance from subtalar joint to the osteotomy, and the lateral step at the osteotomy evaluated by CT scans. Results: Three of the 18 feet examined had tibial nerve palsy at a mean follow-up of 51 months. The mean reduction in tarsal tunnel volume when comparing the contralateral nonoperated foot to the foot operated with LCO was 2732 mm3 in the group without neurological deficit and 2152 mm3 in the group with neurological deficit (P = .60). Conclusion: 3 of 18 feet had tibial palsy as a complication to LCO. We were not able to show that a larger decrease in the tarsal tunnel volume, a more anterior calcaneal osteotomy, or a larger lateral shift of the osteotomy is associated with tibial nerve palsy. Levels of Evidence: Level IV: Retrospective case series.

Endoscopic Transfer of Flexor Hallucis Longus Tendon for Chronic Achilles Tendon Rupture: Technical Aspects and Short-Time Experiences.

BACKGROUND: Chronic Achilles tendon ruptures can lead to reduced power of plantar flexion in the ankle with impaired gait ability. The open 1- or 2-incision technique for flexor hallucis longus transfer has proven good functional outcome but has the disadvantage of relatively extensive surgery performed at a vulnerable location. To reduce the risk of soft tissue problems, the flexor hallucis longus transfer can be performed endoscopically. MATERIAL AND METHOD: An endoscopic technique for flexor hallucis longus transfer is presented together with the experiences from the first six patients operated with this method. RESULTS: No wound healing problems or infections. Five of 6 patients managed single leg heel raise on the affected side 12 months after surgery. CONCLUSION: The functional results are promising. The soft tissue dissection is minor, and no patients had postoperative wound healing problems or infection. Endoscopic flexor hallucis longus transfer may be an operative procedure that can be considered also in patients with potential wound healing problems. LEVELS OF EVIDENCE: Level IV: Technical note/case series without controls.