Tarsal Tunnel Syndrome Outcomes Mr M Aly, Mr P Dearden, Mr S Sturdee, Mr G Wells, Mr A Shenolikar

Overview Background Audit standards Methodology Results Conclusions Anatomy Diagnosis Management Audit standards Methodology Results Conclusions Recommendations

Background Post traumatic compression of the posterior tibial nerve described by Pollock and Davis as early as 1933 The expression "tarsal tunnel syndrome" was coined by Keck in a case report 1962 Tarsal tunnel compression syndrome recommended in differential diagnosis of pain and paraesthesia in the sole of the foot by Keck and Lam independently 1,2

Background Tibial nerve divides within tarsal tunnel Compressive neuropathy of the tibial nerve within the fibro osseous tibial tunnel Located posterior and inferior to the medial malleolus Tibial nerve divides within tarsal tunnel Medial/lateral plantar Calcaneal branch

Anatomy Boundaries Contents Tib post, FHL, and FDL tendons Superficially Flexor retinaculum (laciniate ligament) Deep Medial talus, medial calcaneus, and Sustentaculum tali Inferiorly Abductor hallucis Numerous septa subdivide the tunnel Contents Tib post, FHL, and FDL tendons Posterior tibial artery, Post tibial nerve Venae comitantes (tortuous veins)

Background Potential causes of tarsal tunnel syndrome 3 include: Trauma (17% - 43%) Varicosities (17%) Arthosis Tenosynovitis Rheumatoid Hindfoot deformity Ganglia (8%) Space-occupying lesions (Rare) Idiopathic (10%)

Background Rare condition Frequently under diagnosed Accurate diagnosis difficult as similar symptoms to other lower limb conditions Surgical treatment may benefit patients with definite nerve entrapment Diagnosis aided by thorough history, examination and investigation 4

Diagnosis History Pain over tarsal tunnel + radiation to medial longitudinal arch, plantar surface and heel Often exacerbated by foot position, walking or prolonged standing Relieved by rest / elevation Night symptoms not uncommon

Diagnosis Examination Pain on deep palpation over tarsal tunnel Positive Tinel’s sign often present Sensory changes in distribution of terminal branches of posterior tibial nerve Palpable masses representing extrinsic compression Toe contractures and weak foot intrinsics are chronic signs

Diagnosis Investigation Plain X-ray useful identifying structural abnormality / deformity USS used to identify ganglia, varicosities, lipoma, tenosynovitis NCS and EMG essential adjuvant to history + examination False –ve studies not uncommon and do not rule out tarsal tunnel syndrome 3

Treatment In patients with confirmed compression of nerve surgery is recommended if no response to 3/12 non-operative treatment Surgical outcomes are variable Reported good outcomes in 44% -91% 4-6 No prospective analysis of non-operative treatment

Audit Standards All patients should have nerve conduction studies as ‘Gold standard’ investigation Those with atypical symptoms / presentation should have further imaging (USS/MRI) Outcomes of surgery should be comparable to with low complication rate

Methodology Retrospective case note review Patient group identified from AS2/WLS/SS surgical logbook Notes reviewed using standardised data collection proforma Patients contacted by telephone and outcome scores calculated using AFAOS score

Results Demographics Surgery April 2008 to April 2012 34 ankles in 30 patients 14 Female : 16 Male 18 Left : 15 Right Surgery April 2008 to April 2012 Follow up of 12-60 months (mean 36)

Results Duration of symptoms (34 ankles) Tinel’s sign 18 with symptoms for >12 month duration Remaining 16 cases average symptom duration of 4.6 months Tinel’s sign + ve 18 pts - ve / not documented 15

Results 100 % cases pre-operative NCS Further diagnostic imaging 94% positive suggestive Tarsal tunnel syndrome 53% positive EMG study Further diagnostic imaging 4 MRI 2 USS 1 Isotope bone scan

Results Operative findings – 33 op notes 7 cases tight flexor retinaculum 2 cases engorged veins in tarsal tunnel 1 ganglion within tarsal tunnel 1 subtalar OA with osteophytes 1 nerve entrapment in scar of prev ankle athrodesis 1 incidental Mortons neuroma on MRI excised at time of tarsal tunnel surgery

Results Clinic letter reported outcomes 24 cases good outcome 79% 3 cases slight improvement 7 cases no improvement in symptoms 21%

Results Association of Foot and Ankle Surgery Outcome Survey (midfoot) Patients contacted by telephone Asked to report current symptoms 24/30 patients contactable

Results – Outcome Survey

Results

Results

Results Nil or mild pain in 63% patients No or mild limitations in recreational activities in 63% patients 54% could walk more than 6 blocks (1/3 mile) No difficulty with uneven terrain (stairs, hills, etc.) reported in 41%

Results 7 patients not satisfied: 2 had 12+ months symptoms 1 had 12+ months symptoms and a negative NCS 3 had pathology within the tarsal tunnel (2 x engorged veins / 1 x ganglion) Final 1 patient had concurrent L4-5 radiculopathy

Results - Complications Superficial wound infection 4 cases (12%) - (3 diagnosed and treated by GP) All resolved with PO Abx Wound dehiscence 1 case (3%) Resolved + healed with dressings only Recurrance 2 cases Revision surgery planned in 1 but never undertaken

Conclusions All patients underwent pre-op NCS as per recommendation in literature Results of surgical treatment at HRI/CRH comparable with that reported in the literature (79% good outcome)

Recommendations Review of current outcomes of non-operative treatment Pre-operative scoring to allow more accurate analysis of outcomes Patient advice leaflets explaining condition and its treatment

References Keck C: The tarsal-tunnel syndrome. J. Bone Joint Surg 1962, 44A:180–2. Lam SJS: A tarsal-tunnel syndrome. Lancet 1962; 2: 1354–5. Antoniadis G, Scheglmann K. Posterior tarsal tunnel syndrome: diagnosis and treatment. Dtsch Arztebl Int. 2008 Nov;105(45):776-81. Ahmad M, Tsang K, Mackenney PJ, Adedapo AO. Tarsal tunnel syndrome: A literature review. Foot Ankle Surg. 2012 Sep;18(3):149-52. Singh S, Wilson M, Chiodo: The surgical treatment of tarsal tunnel syndrome: Review. The Foot 15 (2005) 212–216. Ballie DS, Kelinkian AS: Tarsal tunnel syndrome: Diagnosis, surgical technique, and functional outcome. Foot Ankle Int 1998; 19: 65–72.