Tibialis Posterior Tendon Dysfunction
Treatment
NON OPERATIVE
- Indications
- attempted for all patients with symptomatic dysfunction ofPTT
- stage 1 disease
- functioningPTT but clinical synovitis
- Orthotic
- Initial 6 weeks
- short leg cast
- cam walker
- Allow to weight bear in cast
- After 6 weeks
- Medial wedge
- Outside iron with medial T strap
- NSAIDS
- Stage 2-4
- In the sedentary patient with non functioningPTT
- Moulded AFO
- prevents progression of deformity & alleviates symptoms
- Only consider surgery if the bracing fails
OPERATIVE
- Indications
- Only after bracing failed
- Dependent on
- Age
- Weight
- Activity level
- Extent of deformity
- Principles
- least invasive procedure that decreases pain & improves pain selected
- Procedures
- Soft tissue
- Debridement of tendon & tenosynovectomy
- Bony
- Tenosynovectomy
- Stages
- 1
- nonoperative
- immobilization
- NSAIDs
- Arch support
- Tenosynovectomy at 3 months
- ± FDL transfer
- 2
- Nonoperative
- 67% effective
- Shoe modification
- Medial arch support
- Operative
- debridement & tenosynovectomy + FDL transfer + spring ligament imbrication ± medial displacement calcaneal tuberosity osteotomy ± TAL
- calcaneal osteotomy first, harvests FDL by releasing it from knot of Henry, then decides whether or not to perform medial column shortening, before plicating spring ligament & fixing tendon transfer via Pulvertaft weave
- lateral column lengthening
- calcaneal neck
- CC joint
- Isolated arthrodesis
- 3
- NSAIDS
- AFO
- accomodative
- Shoe modifications
- Operative’
- Triple arthrodesis ± TAL
- Isolated arthrodesis (TN)
- ST arthrodesis ± FDL transfer
- 4
- Pantalar arthrodesis
- Tibiocalcaneal arthrodesis
Tenosynovectomy
- Indications
- 6 weeks of non op treatment failed
- Seronegative arthropathy in young patient to prevent rupture
- Technique
- Posteromedial approach from musculotendinous junction to insertion
- 1cm strip of flexor retinaculum preserved to prevent subluxation of tendon
- Tendon sheath opened
- Inflammatory synovitis debrided
- Fissures debrided & repaired
- 4/0 nonabsorbale
- Bulbous enlargement of tendon resected to allow easy glide around the posterior malleolus
- Leave sheath open
- In the older patient with more significant degeneration should consider procedure to augment thePTT prior to rupture
- Consider side to side tenodesis of FDL toPTT or Calcaneal osteotomy in addition to tenosynovectomy
Calcaneal Osteotomy:
- Principle
- to shift the calcaneum medially & altering the mechanical axis & reducing the valgus thrust on hindfoot
- Redirects pull of the TA to medial side of axis of subtalar joint & reducing valgus
- Indications
- Combined with Tenosynovectomy for advanced Stage 1 disease
- Conjunction with flexor transfer with Stage 2 disease
- Technique
- Lateral decubitus
- Incision
- Lateral
- inferior & parallel to peroneal tendons & posterior to sural n
- Superficial
- Flap is deepened down to bone
- Deep
- Down to periosteum
- Osteotomy
- Transverse osteotomy in calcaneus
- angled 45° to sole of foot
- Lamina spreader inserted to detach the medial soft tissue attachments of calcaneum
- Translation of the posterior fragment medially 10mm & fixed with cannulated cancellous screw
Lateral Column Lengthening
- Indications
- Stage 2 dysfunction with lateral foot pain
- Mobile subtalar joint
- No fixed supination deformity of forefoot when heel held in neutral position
- Generally performed as calcaneocuboid joint arthrodesis
- Procedure
- Options
- lengthening lateral column via tricortical bone graft inserted 1.5cm posterior to calcaneal-cuboid joint
- lengthen lateral column through CC joint, performing arthrodesis at time
Flexor Tendon Transfer:
- Indications
- Stage 1 or 2 disease with
- Weakness
- Valgus angulation of hindfoot
- Pain in medial part of foot
- Mobile subtalar joint
- FDL is prefered to FHL due to
- Closer toPTT
- Further from N-V bundle
- Dissection less complicated
- Donor site morbidity less
- FDL
- FDL is bipennate
- Origin
- both bones of leg
- posterior surface of tibia below soleal line
- fibula via broad aponeurosis
- Path
- tendon forms centrally
- tendon passes superficial to Tibialis Posterior in lower part of leg
- passes over tendon of FHL in foot at knot of Henry (at which point it receives reinforcement to its medial two tendons from FHL)
- four tendons of FDL receive insertions of flexor accessorius at their commencement & then give origin to lumbricals
- Insertion
- They ultimately insert into bases of terminal phalanges
- Innervation
- tibial nerve (S1, S2)
- Technique
- Incisions
- Posteromedial incision
- From musculotendinous junction to navicular
- Tib posterior tendon is cut at level of medial malleolus & also 1cm from its insertion, central part is discarded
- FDL is harvested as distally as possible, passed through vertical drill hole in navicular & sutured to stump of Tibialis Posterior under tension
- capsular plication of talonavicular joint
- imbrication of short spring ligament
- proximal stump of Tibialis Posterior is tenodesed to FDL
- Should only be performed if muscle belly is not fibrosed
- Set midway between maximum tension & complete relaxation
- At end of procedure should rest in slight equinovarus position
- Postop
- 4 weeks NWB in cast
- Then 4 weeks in AFO
- Arthrodesis
- Indications
- PTT dysfunction with pain in lateral border of foot
- Rigid valgus deformity of hindfoot that when corrected to neutral associated with fixed supination deformity of forefoot
- Triple Arthrodesis
- Goals
- Realign the hindfoot
- Plantargrade weight bearing surface
- Maintain integrity of the adjacent joints
- Avoid incisional neuromas
- Technique
- Two incisions
- Ollier with Incision over the T-N joint
- Subtalar & Calcaneocuboid joints resected from lateral incision
- Talonavicular through the medial incision
- Need to indentify area between the cuboid & navicular where all 4 bones are in contact as fusion here ensures stable foot in absence of fusion elsewhere- Jahss -Quadruple arthrodesis
- ORIF with compression screws
- Talonavicular fixed first & this realigns the Subtalar joint that fixed in slight valgus
- When fixing the C-C joint need to elevate the cuboid to prevent sag that may cause pain along the lateral surface of foot
- Better to leave the foot in valgus then neutral or varus
- Results
- Maybe dissapointing due to later ankle problems in adult with fixed flat foot deformity
- talus may tilt into valgus at the tibiotalar joint
- If this is the case then - Primary Tibiotalocalcaneal arthrodesis suggested - Johnson & Lester 1989