Surgical reconstruction of posterior tibial tendon dysfunction: Prospective comparison of flexor digitorum longus substitution combined with lateral column lengthening or medial displacement calcaneal osteotomy
Introduction
The tibialis posterior muscle serves as the primary inverter of the heel and is active from mid-to-terminal stance. Its contraction allows the gastrocnemius–soleus complex to shift to the medial side of the subtalar axis; when the gastrocnemius–soleus contracts, it then becomes a powerful heel inverter. Heel inversion creates obliquity of the transverse tarsal (talo-navicular, calcaneo-cuboid) joint, thereby creating a rigid midfoot during terminal stance, which allows efficient transfer of stored energy in the lower extremity for toe-off and swing phase. Dysfunction of the tibialis posterior muscle results in less efficient gait, as the heel does not effectively medialize upon tibialis posterior contraction, and the gastrocnemius–soleus complex requires greater excursion to initiate heel inversion. In cases where the tibialis posterior muscle no longer contracts, resting heel valgus may be accentuated as the gastroc-soleus complex becomes a deforming force, and its subsequent contraction creates an external valgus moment on the heel. In these cases, the supporting medial soft tissues become attenuated, further accentuating the resultant flatfoot deformity. Late changes with the pathologic flatfoot include lateral hindfoot bony impingement, sinus tarsi inflammation, peroneal tendonitis, equinus contracture, and eventual arthrosis.
Posterior tibial tendon dysfunction (PTTD) was first classified by Johnson and Strom [1] with later modification by Myerson [2]. Stage I PTTD involves inflammation of the tendon with no functional deficiencies. The hindfoot remains supple, and patients are able to perform both double and single heel raises. In stage II PTTD, the hindfoot remains supple, as indicated by the ability to perform a double heel raise; however, patients are not able to perform a single heel raise, indicative of an incompetent tendon. The tendon may remain intact, but is no longer able to adequately contract. With stage III PTTD, the tendon is incompetent and the hindfoot rigid, which is indicative of arthrosis. The patient is not able to invert the heel with a double heel raise. Stage IV dysfunction exhibits additional deltoid ligament incompetence, resulting in varus tilt of the talus within the ankle mortise [11]. More recently, a stage IIb has been described [3]. In this population, the heel is brought to a neutral position, but the midfoot remains in greater than 10° varus, with residual elevation of the medial column.
When PTTD cannot be appropriately addressed through conservative measures (rest, rehabilitation, and/or bracing), surgical intervention is necessary to correct the resulting deformity and restore function of the limb. Currently, most surgeons perform reconstruction/substitution of the dysfunctional posterior tibial tendon (PTT) with transfer of the flexor digitorum longus (FDL) into the navicular tuberosity [4]. Additional soft tissue reconstructive procedures include repair/imbrication of the spring ligament and/or the talo-navicular capsule. In cases with concomitant equinus contracture, either a gastrocnemius recession or tendoAchilles lengthening (TAL) is indicated. While soft tissue reconstruction has been shown to alleviate pain, residual pes planovalgus and midfoot abduction frequently remain [5]. The medial displacement calcaneal osteotomy (MDCO) provides both static and dynamic correction by medialization of the calcaneal insertion of the gastroc-soleus complex, thereby allowing for initiation of heel inversion by the PTT and more effective function of the gastroc-soleus complex as a powerful secondary heel inverter. The MDCO has been shown to improve patients’ function and radiographic parameters [6], [7], [8], [9]. Similarly, other authors have recommended the use of lateral column lengthening (LCL), either through the anterior neck of the calcaneus, or with lateral column lengthening fusion (LCLF) of the calcaneo-cuboid joint, for correction of pes planovalgus and midfoot abduction [10], [11], [12], [13]. Comparable patient satisfaction and radiographic improvement have been noted with this technique. No published study has compared these different osteotomies for the surgical treatment of PTTD.
The development of multisegmental foot and ankle models has allowed for more precise quantitative clinical assessment of pathologic gait [14], [15], [16], [17], [18], [19], and recent application of such models in patients with PTTD have demonstrated a powerful capacity for characterization of the pathology [20], [21], [22], [23], [24], [25]. It was the intent of this study to extend these multisegmental kinematic measures to a post-operative population and compare outcomes from two different surgical procedures.
This is a follow-up study to a previous characterization of patients with PTTD who were assessed prior to surgical intervention [26]. In this study, 20 patients with PTTD underwent either reconstruction/substitution of the PTT with an FDL tendon transfer combined with MDCO (“MDCO group”), or PTT/FDL reconstruction combined with MDCO and lateral column lengthening through the anterior neck of the calcaneus or calcaneo-cuboid lengthening fusion (“LCL group”) [4]. Both populations were compared to a previously assessed healthy population (13 males, 12 females; 41.3 ± 12.5 years) [27], [28]. Additional radiographic evaluations were performed to measure correction of pre-operative pes planovalgus and abduction deformities. We hypothesized that both procedures would provide comparable improvements in temporal–spatial parameters, but that patients receiving lateral column lengthening (LCL group) would demonstrate more inversion post-operatively compared to the MDCO group.
Section snippets
Materials and methods
This was a prospective study of 20 patients (21 feet, with one subject tested bilaterally; Table 1). They are a subset of 33 patients treated between May 1999 and November 2005, and represent a consecutive sample of patients meeting the inclusion criteria who were willing to commit to pre- and post-operative visits for gait testing. Patients were eligible for the study based on a diagnosis of PTTD stage II or IIb and failed prior nonoperative treatment (minimum 6 months). Exclusion criteria
Demographics
Analysis of subject demographics demonstrated differences in age (MDCO group: 49.1 ± 7.5 years; LCL group: 59.0 ± 8.9 years) and height (MDCO group: 1.7 ± 0.1 m; LCL group: 1.6 ± 0.1 m), but no significant differences in weight, BMI, or follow-up time. The results of demographic analysis are presented in Table 1.
Temporal–spatial parameters
Temporal–spatial parameters were comprised of stride length, cadence, walking speed, and stance/swing ratio. Analysis of pre-operative data found significant differences between each group and
Discussion
The surgical treatment of stage II PTTD requires FDL tendon transfer, combined with additional soft tissue repair of the spring ligament and talo-navicular capsule as indicated. Original reconstruction procedures relied solely on these soft tissue procedures, which provided good pain relief, but failed to correct pre-operative deformity in 35% of patients [3]. It is now recognized that corrective calcaneal osteotomy is required to improve the height of the medial longitudinal arch, as well as
References (39)
- et al.
The role of osteotomies in the treatment of posterior tibial tendon disorders
Foot Ank Clin
(1997) - et al.
Kinematic analysis of a multi-segment foot model for research and clinical applications: a repeatability analysis
J Biomech
(2001) - et al.
Pathomechanics of posterior tibial tendon insufficiency
Foot Ankle Clin
(1997) - et al.
Changes in gait associated with acute stage II posterior tibial tendon dysfunction
Gait Posture
(2007) - et al.
Three-dimensional kinematics of the forefoot, rearfoot, and leg without the function of tibialis posterior in comparison with normals during stance phase of walking
Clin Biomech
(1999) - et al.
Foot and ankle kinematics in patients with posterior tibial tendon dysfunction
Gait Posture
(2008) - et al.
Preoperative gait characterization of patients with ankle arthrosis
Gait Posture
(2006) - et al.
Operative treatment of the difficult stage 2 adult acquired flatfoot deformity
Foot Ankle Clin
(2001) - et al.
Effects of age on the biomechanics and physiology of gait
Clin Geriatr Med
(1996) - et al.
Predicting peak kinematic and kinetic parameters from gait speed
Gait Posture
(2003)
Influence of walking speed on gait parameters
J Biomed Eng
Tibialis posterior tendon dysfunction
Clin Orthop
Adult acquired flatfoot deformity: treatment of dysfunction of the posterior tibial tendon
Instr Course Lect
Non-operative management of posterior tibialis tendon dysfunction: design of a randomized clinical trial [NCT00279630]
BMC Musculoskelet Disord
Surgery of the foot and ankle
Rupture of the posterior tibial tendon causing flat foot. Surgical treatment
J Bone Joint Surg Am
Intermediate term follow-up of calcaneal osteotomy and flexor digitorum longus transfer for treatment of posterior tibial tendon dysfunction
Foot Ankle Int
Treatment of stage II posterior tibial tendon deficiency with flexor digitorum longus tendon transfer and calcaneal osteotomy
Foot Ankle Int
Treatment of posterior tibial tendon dysfunction with flexor digitorum longus tendon transfer and calcaneal osteotomy
Orthopedics
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2020, Gait and PostureCitation Excerpt :This alteration in the mid/hindfoot structure with decreased rigidity (unlocked bones) could affect sagittal plane motions. Indeed, several studies have found decreased stride length, cadence, and walking speed for PTTD gait [10,24,48]. Furthermore, other studies reported decreased sagittal plane ankle joint power for PTTD [29,32].