Interference screw for fixation of FDL transfer in the treatment of adult acquired flat foot deformity stage II

A Novel Anatomic Reconstruction for Posterior Tibialis Tendon in Treatment of Flexible Adult-Acquired Flatfoot Deformity

OBJECTIVE

To present a novel approach for the anatomic reconstruction of the posterior tibialis tendon (PTT) in restoring plantar insertions and evaluate its efficiency in treating flexible adult-acquired flatfoot deformity (AAFD) caused by PTT dysfunction.

METHODS

For AAFD treatment, a novel PTT reconstruction method was presented. The current study involved 16 patients, including three men, and 13 women, from August 2017 to July 2019. The mean age was 43.2 ± 15.1 years (21-64 years). The innovative PTT repair method was used on all patients. The treatment involved performing a traditional Flexor Digitorum Longus (FDL) transfer in the navicular tuberosity and suturing the plantar insertions to FDL as tension was applied to tighten the plantar structures of the foot. The results were retrospectively analyzed. The clinical outcome was assessed using the pain visual analogue scale (VAS), the satisfaction VAS, and the American Orthopedic Foot and Ankle Society ankle-hindfoot scale (AOFAS-AH). Isokinetic testing was performed using a dynamometer at 60°/s and 120°/s for inversion/eversion and plantarflexion/dorsiflexion, respectively, to determine the mean peak torque. Radiographic measurements were employed to assess the outcomes.

RESULTS

Bone surgeries combined with the modified anatomic PTT reconstruction were performed on patients with medializing calcaneal osteotomy in 12 (75%) patients and subtalar joint fusion in four (25%) patients. The branch linking to the plantar insertions was detected in every case, with an average width of 3.5 ± 0.8 mm (3.1-4.3 mm). All patients were followed up for the mean of 16.8 ± 1.8 months (range, 15-20 months). The average postoperative functional scores, including pain VAS, satisfaction VAS, total AOFAS-AH, and all AOFAS-AH sub-scales, steadily improved during the follow-up. In the last follow-up, isokinetic testing revealed no loss of plantarflexion strength (p = 0.350 and 0.098) and significant improvement in the inversion strength (p = 0.007 and 0.008) in the operated ankles at 60°/s and 120°/s. Radiographic outcomes, particularly the talar head uncovering, improved significantly after more than a year (p < 0.001 for all).

CONCLUSIONS

The novel technique for PTT reconstruction in restoring the plantar insertions serves as an effective procedure in treating AAFD caused by PTT dysfunction in terms of delivering a consistent improvement in ankle inversion strength, medial longitudinal arch restoring, and satisfactory clinical outcomes.

Systematic review of tendon transfers in the foot and ankle using interference screw fixation: Outcomes and safety of early versus standard postoperative rehabilitation

AIMS

To compare the outcomes of early and standard rehabilitation protocols following tendon transfers in the foot and ankle using interference screw fixation (ISF).

METHODS

A systematic review was performed for relevant articles (1998 to 2020) reporting foot tendon transfer using ISF in adults. The primary outcome was early tendon failure. Secondary outcomes included function and complications.

RESULTS

In total, 21 studies met the inclusion criteria, totalling 494 patients. Seven studies reported early rehabilitation protocols. The rate of early tendon failure was zero for each protocol and studies consistently reported a significant improvement in function. No differences were found comparing different rehabilitation protocols for tendon transfer for Achilles tendon pathology and foot drop.

CONCLUSION

Both early and standard rehabilitation protocols are associated with high patient satisfaction and low complication rates, but currently there is a lack of evidence to support early loaded activities or motion.

LEVEL OF EVIDENCE

IV Systematic review including case series.

Medial displacement calcaneal osteotomy versus lateral column lengthening to treat stage II tibialis posterior tendon dysfunction, a prospective randomized controlled study

PURPOSE

Adult-acquired flatfoot deformity (AAFD) requires optimum planning that often requires several procedures for deformity correction. The objective of this study was to detect the difference between MDCO versus LCL in the management of AAFD with stage II tibialis posterior tendon dysfunction regarding functional, radiographic outcomes, efficacy in correction maintenance, and the incidence of complications.

PATIENT AND METHODS

42 Patients (21 males and 21 females) with a mean age of 49.6 years (range 43-55), 22 patients had MDCO while 20 had LCL. Strayer procedure, spring ligament plication, and FDL transfer were done in all patients. Pre- and Postoperative (at 3 and 12 months) clinical assessment was done using AOFAS and FFI questionnaire. Six radiographic parameters were analyzed, Talo-navicular coverage and Talo-calcaneal angle in the AP view, Talo- first metatarsus angle, Talo-calcaneal angle and calcaneal inclination angle in lateral view and tibio-calcaneal angle in the axial view, complications were reported.

RESULTS

At 12 months, significant improvement in AOFAS and FFI scores from preoperative values with no significant difference between both groups. Postoperative significant improvements in all radiographic measurements in both groups were maintained at 12 months. However, the calcaneal pitch angle and the TNCA were better in the LCL at 12 months than MDCO, 17̊±2.8 versus 13.95̊±2.2 (p=0.001) and 13.70̊±2.2 versus 19.05̊±3.2 (p<0.001) respectively. 11 patients (26.2%) had metal removal, seven (16.6%) in the MDCO, and four (9.6%) in the LCL. Three (7.1%) in the LCL group had subtalar arthritis, only one required subtalar fusion.

CONCLUSION

LCL produced a greater change in the realignment of AAFD, maintained more of their initial correction, and were associated with a lower incidence of additional surgery than MDCO, however, a higher incidence of degenerative change in the hindfoot was observed with LCL.

Flexor digitorum longus tendon transfer to the navicular: tendon-to-tendon repair is stronger compared with interference screw fixation

PURPOSE

To assess whether early rehabilitation could be safe after flexor digitorum longus (FDL) tendon transfer, the current biomechanical study aimed to measure tendon displacement under cyclic loading and load to failure, comparing a traditional tendon-to-tendon (TT) repair with interference screw fixation (ISF).

METHODS

24 fresh-frozen cadaveric below knee specimens underwent FDL tendon transfer. In 12 specimens a TT repair was performed via a navicular bone tunnel. In a further 12 specimens ISF was performed. Using a materials testing machine, the FDL tendon was cycled 1000 times to 150 N and tendon displacement at the insertion site measured. A final load to failure test was then performed. Statistical analysis was performed using two-way ANOVA and an independent t test, with a significance level of p < 0.05.

RESULT

No significant difference in tendon displacement occurred after cyclic loading, with mean tendon displacements of 1.9 ± 1.2 mm (mean ± SD) in the TT group and 1.8 ± 1.5 mm in the ISF group (n.s.). Two early failures occurred in the ISF group, none in the TT group. Mean load to failure was significantly greater following TT repair (459 ± 96 N), compared with ISF (327 ± 76 N), p = 0.002.

CONCLUSION

Minimal tendon displacement of less than 2 mm occurred during cyclic testing in both groups. The two premature failures and significantly reduced load to failure observed in the ISF group, however, indicate that the traditional TT technique is more robust. Regarding clinical relevance, this study suggests that early active range of motion and protected weight bearing may be safe following FDL tendon transfer for stage 2 tibialis posterior tendon dysfunction.

Return to sport activities after medial displacement calcaneal osteotomy and flexor digitorum longus transfer

PURPOSE

Medial displacement calcaneal osteotomy with flexor digitorum longus transfer is a common treatment for the management of the adult flatfoot associated with posterior tibial tendon dysfunction. In the literature, there is a paucity of information regarding the ability of patients to return to sport and recreational activities after this surgical procedure. The purpose of this retrospective clinical study was to assess the rate and type of athletic activities that patients participated in before and after medial displacement calcaneal osteotomy with flexor digitorum longus transfer.

METHODS

A consecutive series of 42 patients with a mean age at surgery of 41 years (range 19-74 years) was evaluated with a minimum follow-up of 24 months (range 18-31 months). Pre- and post-operative sporting activities were assessed. At final follow-up, patients were asked to complete a Sports Athlete Foot and Ankle Score (SAFAS). Each patient was also evaluated with weight-bearing radiographs of the foot before surgery and at final follow-up.

RESULTS

Preoperatively, 27 of 42 (64.3 %) patients were engaged in athletic activities, participating in an average of 1.4 h/week (range 0-6 h/week); post-operatively, 36/42 (85.7 %) participated in sport and recreational activities for an average of 3.5 h/week (range 0-15 h/week). Meary's angle improved significantly from 11.5 ± 6.2 degrees preoperatively to 7.0 ± 5.7 degrees at final follow-up (p < 0.01); calcaneal pitch improved significantly from 16.5 ± 4.6 degrees to 19.0 ± 5.0 degrees (p < 0.01). At final follow-up, patients demonstrated good SAFASs in symptom tolerance (86.4 %), pain tolerance (89.0 %), daily living performance (96.1 %), and sports performance (86.7 %).

CONCLUSION

The majority of patients returned to sports and recreational activity after medial displacement calcaneal osteotomy and flexor digitorum longus for the treatment of adult flatfoot associated with posterior tibial tendon dysfunction.

LEVEL OF EVIDENCE

III.

Anatomical Study of the Neurovascular in Flexor Hallucis Longus Tendon Transfers

The transfer of the flexor hallucis longus tendon or flexor digitorum longus tendon is frequently used for the treatment of posterior tibial tendon insufficiency or chronic Achilles tendinopathy. According to several anatomical studies, harvesting the flexor hallucis longus (FHL) tendon may cause nerve injury. Sixty-eight embalmed feet were dissected and anatomically classified to define the relationship between Henry’s knot and the plantar nerves. Two different configurations were identified. In Pattern 1, which was observed in 64 specimens (94.1%), the distance between the medial plantar nerve and Henry’s knot was 5.96 mm (range, 3.34 to 7.84, SD = 1.12). In Pattern 2, which was observed in 4 specimens (5.9%), there was no distance between the medial plantar nerve (MPN) and Henry’s knot. No statistically significant difference was observed according to gender or side (p > 0.05). A retraction was performed to harvest the FHL through the posteromedial hindfoot incision using a single minimally invasive technique, and the medial and lateral plantar nerve lesions were scrupulously assessed. In conclusion, medial and lateral plantar nerve injuries did not occur more frequently, even after performing a single minimally invasive incision to harvest the FHL tendon, due to the large distance between the FHL tendon and the medial and lateral plantar nerves.

CT and MR Imaging of the Postoperative Ankle and Foot

A variety of surgical procedures exist for repair of both traumatic and degenerative osseous and soft-tissue pathologic conditions involving the foot and ankle. It is necessary for the radiologist to be familiar with these surgical procedures, so as to assess structural integrity, evaluate for complicating features, and avoid diagnostic pitfalls. Adequate interpretation of postoperative changes often requires access to surgical documentation to evaluate not only the surgery itself but the expected timeline for resolution of normal postoperative changes versus progressive disease. Appropriate use of surgical language in radiology reports is another important skill set to hone and is instrumental in providing a high-quality report to the referring surgeons. The pathophysiology of a myriad of surgical complaints, beginning from the Achilles tendon and concluding at the plantar plate, are presented, as are their common appearances at computed tomography and magnetic resonance imaging. Commonly encountered entities include Achilles tendon tear, spastic equinus, nonspastic equinus, talar dome osteochondral defect, tarsal tunnel syndrome, plantar fasciitis, pes planovalgus, pes cavovarus, peroneal tendinosis, lateral ligament complex pathology, Morton neuroma, plantar plate tear, and metatarsophalangeal joint instability. Computer-generated three-dimensional models are included with many of the procedures to provide a more global view of the surgical anatomy. Correlation with intraoperative photographs is made when available. When appropriate, discussion of postoperative complications, including entities such as infection and failure of graft integration, is presented, although a comprehensive review of postoperative complications is beyond the scope of this article. Notably absent from the current review are some common foot and ankle procedures including hallux valgus and hammertoe corrections, as these are more often evaluated radiographically than with cross-sectional imaging. ^©RSNA, 2016.