The Effect of Tibiotalar Joint Line Level Alterations on Tibiotalar Range of Motion Following Total Ankle Arthroplasty.

BACKGROUND: The effect of tibiotalar joint line level (TTJL) on patient outcomes following total ankle arthroplasty (TAA) remains unclear. It was previously reported that patients with end-stage ankle arthritis have an elevated TTJL compared with nonarthritic ankles, and the TTJL post-TAA remains elevated compared with nonarthritic ankles. The objectives of this study were to (1) propose a reliable radiographic method to measure the TTJL absolute value and (2) determine the effect of TTJL alterations on tibiotalar range of motion (ROM) following TAA. METHODS: A retrospective review was performed on patients who underwent TAA between January 2018 and April 2021 with a minimum of 1-year postoperative follow-up and complete perioperative ROM radiographs. Radiographic TTJL and ROM measurements were performed by 2 observers. The proposed TTJL measuring technique computes 4 measurements: high, low, center of the talus (center), and center of the axis (axis). Reliability of measurements and correlation between TTJL measurements and ROM were assessed. RESULTS: A total of 33 patients were included. Postoperatively, 22 patients had a lowered TTJL compared to 11 patients with an elevated TTJL (2.2 ± 1.3 mm lowered vs 1.9 ± 1.2 mm elevated; P < .0001). Of the 4 TTJL measurements, 3 (low, center, axis) demonstrated a significant positive correlation between lowering the TTJL and improved tibiotalar dorsiflexion and 2 (low, axis) for total ROM (all P < .05). Plantarflexion was not significantly affected by TTJL alterations. Compared to patients with an elevated TTJL, patients with a lowered TTJL had improved tibiotalar dorsiflexion (8.8 vs 2.5 degrees; P = .0015) and total ROM (31.0 vs 22.9 degrees; P = .0191), respectively. The interrater reliability was nearly perfect (intraclass correlation r = 0.96-0.99). CONCLUSION: In this small series, we found that lowering the TTJL level may more closely reestablish the native TTJL and correlates with improved tibiotalar dorsiflexion and total ROM following TAA. LEVEL OF EVIDENCE: Level IV, case series.

First Tarsometatarsal Alignment May Self-Correct After Triple Arthrodesis in Progressive Collapsing Foot Deformity.

BACKGROUND: Triple arthrodesis is commonly used to correct rigid progressive collapsing foot deformity (PCFD). These patients often have associated first tarsometatarsal (TMT) instability on lateral weightbearing radiographs. It has not been well established if it is necessary to add first TMT arthrodesis to adequately correct the overall deformity. This study retrospectively examined pre- and postoperative radiographs of PCFD patients with first TMT instability that were managed by triple arthrodesis alone. METHODS: All triple arthrodesis cases were searched for a single surgeon between 2013 and 2021. Inclusion criteria were patients with PCFD who underwent triple arthrodesis without first TMT joint fusion. Preoperative radiographs were examined for first TMT joint instability, demonstrated by plantar gapping of the first metatarsal-medial cuneiform angle or first metatarsal dorsal subluxation at the TMT joint. Measurement of sagittal first metatarsal-medial cuneiform angle and first metatarsal subluxation as described by King and Toolan was performed. RESULTS: Twenty patients satisfied the inclusion criteria. Six patients did not demonstrate at least 30% improvement of one or both measurements of first TMT instability postoperatively and were considered failures. Fourteen patients demonstrated correction of their first TMT joint instability. Average follow-up was 5.0 (range, 1.8-9.4) years. The first metatarsal-medial cuneiform angle improved from 3.8 to 1.1 degrees (P < .05). The first metatarsal subluxation corrected from 4.1 to 1.5 mm (P < .05). One patient showed radiographic evidence of arthritis in the first TMT joint at final follow-up. CONCLUSION: Seventy percent of patients with PCFD with asymptomatic first TMT joint instability demonstrated correction of first TMT radiographic instability with isolated triple arthrodesis. This was maintained at 5-year mean follow-up. In cases of PCFD with medial column instability, triple arthrodesis alone may be adequate to restore overall alignment.

Suitability of Minced Cartilage From Osteochondral Lesions of the Talus for Immediate Autograft Reimplantation.

Background: Particulated autograft cartilage implantation is a surgical technique that has been previously described for the repair of osteochondral lesions of the talus (OLT). It uses cartilage fragments harvested from the OLT that are minced into 1-2-mm3 fragments and then immediately reimplanted back into the chondral defect and sealed with fibrin glue during a single-stage surgery. The purpose of this study was to characterize the suitability of these minced cartilage fragments as immediate autograft for the treatment of OLTs. Methods: Thirty-one patients undergoing primary arthroscopic surgery for their OLT consented to have their loose or damaged cartilage fragments removed and analyzed in the laboratory. Harvested specimens were minced into 1- to 2-mm3 fragments and cell count, cell density, and cell viability were determined. In addition, physical characteristics of the OLT lesion were recorded intraoperatively and analyzed including size, location, Outerbridge chondromalacia grade of the surrounding cartilage, density of underlying bone, and whether the surgeon thought the OLT was primarily hyaline or fibrocartilage. Results: An average of 419 000 cells was able to be obtained from the harvested OLT fragments. The cells were 71.2% viable after mincing. Specimens from younger patients and from lesions with worse chondromalacia adjacent to the OLT had significantly higher cell numbers. Those from lateral lesions and with worse neighboring chondromalacia had a significantly higher cell density. None of the remaining physical OLT characteristics studied seemed to significantly affect cell number or viability. Conclusion: A large number of viable cells are available for immediate autografting by removing the loose or damaged cartilage from an OLT and mincing it into 1- to 2-mm3 fragments. These can be reimplanted into the chondral defect in a single-stage surgery. Future clinical studies are needed to determine if the addition of these live autologous cells either alone or in conjunction with other techniques significantly improves the quality of the repair tissue and clinical outcomes. Level of Evidence: Level IV, case series.

Tibiotalocalcaneal arthrodesis with bulk femoral head allograft for salvage of large defects in the ankle.

BACKGROUND: Tibiotalocalcaneal arthrodesis in patients with large segmental bony defects presents a substantial challenge to successful reconstruction. These defects typically occur following failed total ankle replacement, avascular necrosis of the talus, trauma, osteomyelitis, Charcot, or failed reconstructive surgery. This study examined the outcomes of tibiotalocalcaneal (TTC) arthrodesis using bulk femoral head allograft to fill this defect. METHODS: Thirty-two patients underwent TTC arthrodesis with bulk femoral head allograft. Patients who demonstrated radiographic union were contacted for SF-12 clinical scoring and repeat radiographs. Patients with asymptomatic nonunions were also contacted for SF-12 scoring alone. Preoperative, intraoperative, and postoperative factors were analyzed to determine positive predictors for successful fusion. RESULTS: Sixteen patients healed their fusion (50% fusion rate). Diabetes mellitus was found to be the only predictive factor of outcome; all 9 patients with diabetes developed a nonunion. In this series, 19% of the patients went on to require a below-knee amputation. CONCLUSIONS: Although the radiographic fusion rate was low, when the 7 patients who had an asymptomatic nonunion were combined with the radiographic union group, the overall rate of functional limb salvage rose to 71%. TTC arthrodesis using femoral head allograft should be considered a salvage procedure that is technically difficult and carries a high risk for complications. Patients with diabetes mellitus are at an especially high risk for nonunion. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Relative strengths of the calf muscles based on MRI volume measurements.

BACKGROUND: In 1985, Silver et al. published a cadaver study which determined the relative order of strength of the muscles in the calf. Muscle strength, which is proportional to volume, was obtained by dissecting out the individual muscles, weighing them, and then multiplying by the specific gravity. No similar studies have been performed using {\it in vivo} measurements of muscle volume. METHODS: Ten normal subjects underwent 3-Tesla MRI's of both lower extremities using non-fat-saturated T2 SPACE sequences. The volume for each muscle was determined by tracing the muscle contour on sequential axial images and then interpolating the volume using imaging software. RESULTS: The results from this study differ from Silver's original article. The lateral head of the gastrocnemius was found to be stronger than the tibialis anterior muscle. The FHL and EDL muscles were both stronger than the peroneus longus. There was no significant difference in strength between the peroneus longus and brevis muscles. CONCLUSION: This revised order of muscle strengths in the calf based on in vivo MRI findings may assist surgeons in determining the optimal tendons to transfer in order to address muscle weakness and deformity.

Weightbearing CT Analysis of the Transverse Tarsal Joint During Eversion and Inversion.

BACKGROUND: Understanding of the movement and function of the transverse tarsal joint (TTJt) continues to evolve. Most studies have been done in cadavers or under nonphysiologic conditions. Weightbearing computed tomographic (WBCT) scans may provide more accurate information about the position of the TTJt when the hindfoot is in valgus or varus. METHODS: Five volunteers underwent bilateral weightbearing CT scans while standing on a platform that positioned both hindfeet in 20 degrees of valgus and 20 degrees of varus. Each bone of the foot was segmented, and the joint surfaces of the talus, calcaneus, cuboid, and navicular were identified. The principal axes for each joint surface were determined and used to calculate the angles and distances between the bones with the foot in valgus or varus. RESULTS: In the coronal plane, the angle between the talus and calcaneus rotated 17.1 degrees as the hindfoot moved from valgus to varus. The distance between the centers of the talus and calcaneus decreased 7.1 mm. The cuboid translated 3.9 mm medially relative to the calcaneus. There was no change in angle or distance between the cuboid and navicular. The navicular rotated 25.4 degrees into varus relative to the talus. CONCLUSION: The TTJt locking mechanism was previously thought to occur from the talonavicular and calcaneocuboid joint axes moving from parallel to divergent as the hindfoot inverts. The current data show a more complex interaction between the four bones that comprise the TTJt and suggests that the locking mechanism may occur because of tightening of the ligaments and joint capsules. CLINICAL RELEVANCE: This study uses weight bearing CT scans of healthy, asymptomatic volunteers standing on valgus and varus platforms to characterize the normal motion of the transverse tarsal joint of the foot. A better understanding of how the transverse tarsal joint functions may assist clinicians in both the conservative and surgical management of hindfoot pathology.

The Hallux Metatarsophalangeal Capsule: An Anatomic Study With Respect to Percutaneous Hallux Valgus Correction.

BACKGROUND: Minimally invasive surgery for the treatment of hallux valgus deformities has become increasingly popular. Knowledge of the location of the hallux metatarsophalangeal (MTP) proximal capsular origin on the metatarsal neck is essential for surgeons in planning and executing extracapsular corrective osteotomies. A cadaveric study was undertaken to further study this anatomic relationship. METHODS: Ten nonpaired fresh-frozen frozen cadaveric specimens were used for this study. Careful dissection was performed, and the capsular origin of the hallux MTP joint was measured from the central portion of the metatarsal head in the medial, lateral, dorsal, plantarmedial, and plantarlateral dimensions. RESULTS: The ten specimens had a mean age of 77 years, with 5 female and 5 male. The mean distances from the central hallux metatarsal head to the MTP capsular origin were 15.2 mm dorsally, 8.4 mm medially, 9.6 mm laterally, 19.3 mm plantarmedially, and 21.0 mm plantarlaterally. CONCLUSION: The MTP capsular origin at the hallux metatarsal varies at different anatomic positions. Knowledge of this capsular anatomy is critical for orthopaedic surgeons when planning and performing minimally invasive distal metatarsal osteotomies for the correction of hallux valgus. TYPE OF STUDY: Cadaveric Study.

Minimally invasive deltoid ligament reconstruction for stage IV flatfoot deformity.

BACKGROUND: Stage IV is the most advanced form of acquired adult flatfoot deformity (AAFD). It is present when valgus tibiotalar angulation occurs with foot deformities associated with AAFD. Tibiotalocalcaneal or pantalar fusion has been the gold standard for treatment of Stage IV AAFD. However, in some of these patients the tibiotalar deformity is correctable. We sought to determine whether minimally invasive deltoid ligament reconstruction in conjunction with triple arthrodesis (MIDLR/Triple) allows tibiotalar joint sparing surgical therapy in Stage IV-A AAFD patients. MATERIALS AND METHODS: Patients diagnosed with Stage IV-A AAFD were given the option of undergoing ankle joint sparing surgery with the MIDLR/Triple technique. Those that chose this option were followed longitudinally. Eight patients underwent the ankle joint sparing procedure. Average followup was 36 months. Radiographic and functional outcome measures were obtained. Success was defined as maintenance of 3 degrees or less of valgus tibiotalar angulation and greater than 2 mm of lateral joint space remaining at final followup. RESULTS: At final followup, five were judged to have a successful outcome. In those, tibiotalar valgus angulation was reduced from 6.4±2.9 degrees to 2.0±2.0 degrees, lateral ankle joint space was maintained at preoperative levels and SF-12 functional scores were equal to age matched normative scores. The only parameter found to be predictive of successful outcome was the magnitude of preoperative tibiotalar tilt. CONCLUSIONS: MIDLR/triple is a new treatment option that requires significant care in patient selection and surgical execution. It is a choice that allows for preservation of ankle motion in patients diagnosed with Stage IV-A AAFD who have less than 10 degrees of valgus tibiotalar tilt on preoperative standing ankle radiographs.

Driving brake reaction time following right ankle arthrodesis.

BACKGROUND: The purpose of this study was to compare the brake reaction time of patients with successful right ankle fusion to normal volunteers without an ankle fusion. METHODS: Ten patients who underwent successful right ankle arthrodesis were evaluated using a driving simulator as well as an in-shoe pedobarographic measuring system. Brake reaction time, braking force, peak pressure, contact area, and the center of force between the foot and the brake pedal were recorded. SF-12 scores were obtained from all study patients. A control group of ten age-matched individuals without ankle fusion was included for comparison. RESULTS: Mean brake reaction time for the ankle fusion group (0.42+/-0.14 seconds) was significantly slower than for the control group (0.33+/-0.06 seconds) (p=0.03). The center of force was consistently isolated to the forefoot in the ankle fusion group compared to controls who distributed the center of force over both the forefoot and midfoot. There was no significant difference between the ankle fusion and control groups with respect to braking force, peak pressure, or contact area. CONCLUSION: The mean brake reaction time following successful right ankle arthrodesis was significantly slower than that of normal controls. However, the fusion group time was still below the threshold for what is defined as a safe brake reaction time by the United States Federal Highway Administration.

Comparison of initial compression of the medial, lateral, and posterior screws in an ankle fusion construct.

BACKGROUND: One of the requirements for successful ankle arthrodesis is adequate compression by the fixation across the fusion surfaces. A common screw construct for ankle fusion is three crossed screws from proximal-to-distal. Because the screws are inserted nearly orthogonal to each other, it is possible minimal additional compression is obtainable once the first screw is inserted. The aim of this study was to determine which of the three screws gave the greatest initial compression and theoretically should be inserted first. MATERIALS AND METHODS: Seventeen cadaver limbs were dissected to expose the anterior and posterior aspects of the tibiotalar joint. Three Fuji film templates were created for each ankle joint with a hole to accommodate a 7.0-mm cannulated screw. Each film was tested with a single medial, lateral, or posterior screw. The Fuji films were then analyzed for contact area, percent contact area, and pressure. RESULTS: There was no difference in the total contact area, percent contact area, or pressure generated between the three screws. The mean contact area for all screws was 11% of the joint surface. All three screws had greater contact area and percent contact area over the anterior half of the ankle joint. CONCLUSION: The medial, lateral, and posterior screws were equivalent with respect to contact area, percent contact area, and pressure generated across the tibiotalar joint. All three screws had greater contact area over the anterior half of the joint. Only 11% of the tibiotalar joint surface came in contact following the insertion of a single partially threaded screw. CLINICAL RELEVANCE: In a neutrally aligned ankle arthrodesis the order of screw insertion does not affect the amount of compression ultimately achieved at the fusion site.

Effect of Achilles Tendon Lengthening and Gastrocnemius Recession on Radiographic Tibiotalar Motion Following Total Ankle Replacement.

BACKGROUND: Surgeons frequently add an Achilles tendon lengthening or gastrocnemius recession to increase dorsiflexion following total ankle replacement. Previous studies have looked at the effects of these procedures on total tibiopedal motion. However, tibiopedal motion includes motion of the midfoot and hindfoot as well as the ankle replacement. The current study examined the effects of Achilles tendon lengthening and gastrocnemius recession on radiographic tibiotalar motion at the level of the prosthesis only. METHODS: Fifty-four patients with an average of 25 months follow-up after total ankle replacement were divided into 3 groups: (1) patients who underwent Achilles tendon lengthening, (2) patients who had a gastrocnemius recession, (3) patients with no lengthening procedure. Tibiotalar range of motion was measured on lateral dorsiflexion-plantarflexion radiographs using reference lines on the surface of the implants. RESULTS: Both Achilles tendon lengthening and gastrocnemius recession significantly increased tibiotalar dorsiflexion when compared to the group without lengthening. However, the total tibiotalar range of motion among the 3 groups was the same. Interestingly, the Achilles tendon lengthening group lost 11.7 degrees of plantarflexion compared to the group without lengthening, which was significant. CONCLUSION: Both Achilles tendon lengthening and gastrocnemius recession increased radiographic tibiotalar dorsiflexion following arthroplasty. Achilles tendon lengthening had the unexpected effect of significantly decreasing plantarflexion. Gastrocnemius recession may be a better choice when faced with a tight ankle replacement because it increases dorsiflexion without a compensatory loss of plantarflexion. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Painful Accessory Navicular and Spring Ligament Injuries in Athletes.

Painful accessory navicular and spring ligament injuries in athletes are different entities from more common posterior tibialis tendon problems seen in older individuals. These injuries typically affect running and jumping athletes, causing medial arch pain and in severe cases a pes planus deformity. Diagnosis requires a detailed physical examination, standing radiographs, and MRI. Initial treatment focuses on rest, immobilization, and restriction from sports. Orthotic insoles may alleviate minor pain, but many patients need surgery to expedite recovery and return to sports. The authors review their approach to these injuries and provide surgical tips along with expected rehabilitation to provide optimal outcomes.

Assessment of Bony Subfibular Impingement in Flatfoot Patients Using Weight-Bearing CT Scans.

BACKGROUND:: Lateral hindfoot pain in patients with flatfoot deformity is frequently attributed to subfibular impingement. It remains unclear whether this is primarily due to bony or soft-tissue impingement. No studies have used weight-bearing CT scans to evaluate subfibular impingement. METHODS:: Patients with posterior tibial tendonitis were retrospectively searched and reviewed. Subjects had documented flatfoot deformity, posterior tibial tenderness, weight-bearing plain radiographs, and a weight-bearing CT scan. CT scans were evaluated for calcaneofibular impingement on the coronal view and talocalcaneal impingement on the sagittal view. The distance between these structures was measured, along with the sinus tarsi volume. In the second part of this study, 6 normal volunteers underwent weight-bearing CT scans on a platform that held both feet in 20 degrees of varus, followed by 20 degrees of valgus. The same measurements were performed. RESULTS:: Thirty-five percent of flatfoot patients with posterior tibial tendonitis had bony impingement between the fibula and calcaneus on the coronal view. Thirty-eight percent had bony impingement between the talus and calcaneus on the sagittal view. Subjects with bony impingement based on CT scan had significantly higher talonavicular abduction angles on plain radiographs than those without impingement. Sinus tarsi volume decreased by more than half when the subtalar joint moved from varus to valgus in normal controls. CONCLUSION:: Bony subfibular impingement in patients with flatfeet was less common than previously reported. Accurate diagnosis of bony impingement may be useful for surgical decision-making. LEVEL OF EVIDENCE:: Level III, retrospective comparative study.

Fresh osteochondral total ankle allograft transplantation for the treatment of ankle arthritis.

BACKGROUND: Fresh osteochondral total ankle allograft transplantation has been reported in the literature with survival rates between 50% and 92% at 1- to 12-years followup. The goal of this study was to present the results of total ankle allografts from another institution. MATERIALS AND METHODS: Twenty-nine patients underwent osteochondral total ankle transplant at our institution between July 2003 and July 2005. The mean patient age was 41 years old and the mean followup duration was 2 years. RESULTS: At followup, 14 of the 29 transplants had been revised to a repeat ankle transplant, prosthetic total ankle arthroplasty, or bone block arthrodesis. In addition, 6 of the remaining 15 transplants were deemed to be radiographic failures due to allograft fracture, allograft collapse, or progressive loss of joint space. The remaining 9 allografts (31%) were considered successes. In comparing the success versus the failure group, patients who were older, who had a lower body-mass index, and who had minimal preoperative angular deformity did significantly better. CONCLUSION: This is the largest series of osteochondral total ankle allograft transplants reported in the literature to date. There is an extremely high rate of failure associated with this procedure, and we currently consider it only rarely in patients who are too young for ankle replacement, have excellent range of motion, low body mass index, normal radiographic alignment, and who refuse arthrodesis.

Percutaneous screw configuration versus perimeter plating of calcaneus fractures: a cadaver study.

BACKGROUND: Percutaneous screw configuration has been used clinically to reduce the high rate of wound complications associated with the extensile approach of standard open reduction and internal plate fixation. The aim of this cadaveric biomechanical study was to compare the strength of the standard perimeter plating with that of the percutaneous screw configuration for a Sanders type-2B calcaneus fracture. MATERIALS AND METHODS: Ten pairs of fresh-frozen cadaveric lower limbs were prepared and osteotomized to create a Sanders type-2B fracture. Of each pair, one specimen underwent open reduction and internal fixation with standard perimeter plating; the other was stabilized with the percutaneous screw configuration. Each foot was compressed axially via the talar dome (1 mm/sec) until failure occurred. Differences in treatment groups were analyzed for significance (p < 0.05) using paired t-tests. RESULTS: Construct stiffness was 158 +/- 85 and 113 +/- 60 N/mm for the plate and percutaneous fixation, respectively (p = 0.18). Failure occurred at an average of 1156 +/- 513 and 1064 +/- 540 N for the plate and percutaneous construct, respectively (p = 0.65). CONCLUSION: The results suggest that open reduction and internal fixation with percutaneous screw configuration for Sanders type-2B calcaneus fractures provides a strength similar to that of perimeter plating. CLINICAL RELEVANCE: Percutaneous screw fixation of calcaneus fractures may provide fracture reduction similar to plate fixation.

Radiographic comparison of sagittal plane stability between cast and boots.

BACKGROUND: The importance of postoperative stability when considering surgery on the foot and ankle cannot be overestimated. To our knowledge, no literature exists to describe the radiographic sagittal plane motion with varying types of immobilization devices. The purpose of this study was to evaluate the sagittal plane range of motion allowed in different types of boots in comparison to fiberglass cast treatment on normal human subjects. MATERIALS AND METHODS: Ten healthy volunteers without preexisting foot and ankle pathology were chosen for the study. Five types of immobilization were selected for testing, including 4 off-the-shelf braces and a fiberglass cast. Maximum dorsiflexion and maximum plantarflexion lateral radiographs were taken without any immobilization and in the fiberglass cast and all walkers. RESULTS: The mean range of motion in a fiberglass cast was 8.4 degrees (SD, 4.3 degrees); FP Foam Walker, 16 degrees (SD, 6.7 degrees); XP Pneumatic Walker, 15.4 degrees (SD, 5.6 degrees); Donjoy Max Walker, 19.1 degrees (5.4 degrees); and the SP Walker, 39 degrees (SD, 10.7 degrees). The cast was noted to have a significantly greater limitation of sagittal plane motion compared to all other forms of immobilization (p < 0.05). CONCLUSION: Sagittal plane motion is restricted significantly more with a fiberglass cast compared to the FP Foam Walker, and XP Pneumatic Walker, Donjoy Max Walker, and the SP Walker. Therefore, in patients whom maximum restriction of sagittal plane motion is required, use of a fiberglass cast offers superior control.

Allograft total ankle replacement--a dead ringer to the natural joint.

For decades, orthopedic surgeons have been looking for practical alternatives to ankle arthrodesis for the treatment of end-stage ankle arthritis. The most popular alternatives available today are total ankle replacement, supramalleolar osteotomy, and ankle distraction arthroplasty. Fresh bipolar osteochondral allograft of the ankle joint has been sporadically reported in the literature as another alternative to ankle fusion. This article examines the basic science supporting the use of this technique, discusses the five case series reported in the literature, and describes the authors' preferred technique and short-term results.

Measuring Visualized Tendon Length in Peroneal Tendoscopy.

BACKGROUND: Despite multiple studies outlining peroneal tendoscopy, no study exists to evaluate how effective tendoscopy is at visualizing the peroneal tendons without missing a lesion. We sought to measure the length of the peroneal tendons that could be visualized using tendoscopy. METHODS: Ten fresh cadaveric specimens were evaluated using standard peroneal tendoscopy techniques. Peroneus longus and brevis tendons were pierced percutaneously with Kirschner wires at the edge of what could be seen through the camera. The tendon sheaths were then dissected and the distances from anatomic landmarks were directly measured. During zone 3 peroneus longus tendoscopy, a more distal portal site was created for the final 5 specimens. RESULTS: The peroneus brevis could be visualized through the entirety of zone 1 and up to an average of 19.5 mm (95% confidence interval, 16.5-22.5) from its insertion onto the base of the fifth metatarsal in zone 2. Peroneus longus could be visualized through the entirety of zones 1 and 2 and up to an average of 9.7 mm from its insertion onto the base of the first metatarsal in zone 3. This distance was decreased significantly with a more distal portal. The muscle belly of peroneus brevis terminated an average of 1.8 mm (-3.7 to 7.3) above the tip of the lateral malleolus. CONCLUSIONS: Despite limitations, these results suggest that the vast majority of the length of the peroneal tendons can be seen during routine peroneal tendoscopy. A more distal skin portal site may improve visualization of zone 3 of peroneus longus. CLINICAL RELEVANCE: This study confirms the ability of peroneal tendoscopy to see the entire tendon length with appropriate portal placement.

Measuring Visualized Joint Surface in Hallux Metatarsophalangeal Arthroscopy.

BACKGROUND: Arthroscopy has been increasingly used to evaluate small joints in the foot and ankle. In the hallux metatarsophalangeal (MTP) joint, little data exist evaluating the efficacy of arthroscopy to visualize the articular surface. The goal of this cadaveric study was to determine how much articular surface of the MTP joint could be visualized during joint arthroscopy. METHODS: Ten fresh cadaveric foot specimens were evaluated using standard arthroscopy techniques. The edges of the visualized joint surface were marked with curettes and Kirschner wires; the joints were then surgically exposed and imaged. The visualized surface area was measured using ImageJ® software. RESULTS: On the distal 2-dimensional projection of the joint surface, an average 57.5% (range, 49.6%-65.3%) of the metatarsal head and 100% (range, 100%-100%) of the proximal phalanx base were visualized. From a lateral view of the metatarsal head, an average 72 degrees (range, 65-80 degrees) was visualized out of an average total articular arc of 199 degrees (range, 192-206 degrees), for an average 36.5% (range, 32.2%-40.8%) of the articular arc. CONCLUSION: Complete visualization of the proximal phalanx base was obtained. Incomplete metatarsal head visualization was obtained, but this is limited by technique limitations that may not reflect clinical practice. CLINICAL RELEVANCE: This information helps to validate the utility of arthrosocpy at the hallux metatarsophalangeal joint.

The single medial approach to triple arthrodesis: a cadaver study.

BACKGROUND: Triple arthrodesis is traditionally done through a two-incision approach. In certain high-risk patients, it may be desirable to do the procedure through a single medial incision to avoid lateral wound healing problems. METHOD: A cadaver study was undertaken to determine the percentage of surface area of each hindfoot joint that could be prepared through a single medial incision. Five cadaver legs were assigned to the single-incision group, and one cadaver leg was used as the "standard" two-incision specimen. RESULTS: Through the single-incision approach, 91% of the talonavicular joint, 91% of the subtalar joint, and 90% of the calcaneocuboid joint could be prepared. These results were comparable to the two-incision cadaver specimen results. CONCLUSIONS: A single-incision medial approach for triple arthrodesis is a safe and effective technique in the management of hindfoot deformity and arthritis in certain high-risk patients.