Die Triple-Arthrodese in der Therapie degenerativer Rückfußfehlstellungen: Klinische, radiologische und pedobarografische Resultate

Talo-navicular and calcaneo-cuboid fusion with PEEK H-pode™ vs. Titanium Maxlock™ locking plates: Comparison of functional and radiographic outcomes

BACKGROUND

Locking plates are increasingly used to achieve hindfoot fusion. The objective of this study was to compare hindfoot fusion outcomes with the PEEK H-pode™ (Biotech™) locking plate and the titanium Maxlock™ (Tornier-Wright™) locking plate.

HYPOTHESIS

A polyetheretherketone (PEEK) H-pode™ locking plate provides similar fusion rates to a titanium Maxlock™ locking plate for talo-navicular and calcaneo-cuboid arthrodesis.

METHODS

We conducted a retrospective comparative study in 39 patients (including 21 [54%] with pes planovalgus and 11 [28%] with neurological equinovarus deformities) who underwent talo-navicular and/or calcaneo-cuboid fusion, usually combined with subtalar fusion. The first 17 patients (January 2014-February 2016) were managed with Maxlock™ locking plates and the next 22 patients (March 2016-August 2018) with H-pode™ locking plates. These two cohorts of consecutive patients were comparable regarding age, sex distribution, body mass index, and comorbidities. At last follow-up more than 1year after surgery, we compared functional scores, pain intensity, and fusion assessed by radiographs and computed tomography (CT) (threshold set at 33%).

RESULTS

Mean follow-up was 42months (range: 34-63months) in the Maxlock™ group and 25months (range: 12-36months) in the H-pode™ group. At last follow-up, the two groups were not significantly different for the mean values of the American Orthopedic Foot & Ankle Society score, European Foot & Ankle Society score, and visual analogue scale pain score. Neither were the two groups significantly different for talo-navicular and calcaneo-cuboid fusion by CT. In the Maxlock™ group, we found non-significant trends towards a higher proportion of patients with talo-navicular nonunion (18% vs. 5% in the H-pode™ group) and weaker talo-navicular fusion in patients with pes planovalgus (60.8% vs. 82.0%, respectively). Radiographic results overestimated the fusion rates.

DISCUSSION

Talo-navicular and calcaneo-cuboid fusion was not significantly different with H-pode™ and Maxlock™ locking plates. CT was more accurate than standard radiography to assess fusion. These results underline the usefulness of PEEK locking plates for talo-navicular and calcaneo-cuboid fusion; moreover, the radiolucency of PEEK facilitates the interpretation of radiographs.

LEVEL OF EVIDENCE

IV.

Synovitis of the Tarsal Canal: An Uncommon Cause of Lateral Heel Pain After Triple Arthrodesis

Lateral heel pain after triple arthrodesis can have numerous causes, including nonunion of the fusion site, hindfoot malalignment, degenerative arthritis in adjacent joints, and deep infection. We present a case of lateral heel pain after triple arthrodesis due to synovitis of the tarsal canal that was successfully treated with anterior subtalar arthroscopy.

Does osteoarthritis of the ankle joint progress after triple arthrodesis? A midterm prospective outcome study

BACKGROUND

Debate exists regarding the effect of triple fusion on the development of osteoarthritis (OA) of the ankle joint. The midterm outcome after triple arthrodesis and the prevalence of OA following triple arthrodesis are reported in this study. The role of alignment in the development of OA was investigated.

METHODS

Seventy five patients (87 feet) were evaluated in 2003 and of these, 48 patients (55 feet) were available for second evaluation in 2008. X-rays of the ankles and feet were made prior to surgery, in 2003 and in 2008, and the level of osteoarthritis (OA) was graded with the Kellgren and Lawrence score. Of all postoperative X-rays, the AP and lateral talo first metatarsal angle X-rays were compared. Also, standardized digital photos were made to assess the geometry/alignment. The Foot Function Index (FFI) and the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score were completed. In order to investigate the role of the underlying alignment on the aggravation of ankle osteoarthritis, patients were divided into a 'varus' and a 'valgus' group based on the indication for surgery.

RESULTS

The outcome scores (AOFAS and FFI) after triple arthrodesis remained stable in the present 7.5-year follow-up study. An important increase of OA of the ankle was not established, 58% of the patients showed no aggravation, 31% one-grade and 2% two-grade increase of OA. A trend was found (P=.063) towards aggravation of OA of the ankle in patients of the varus group with the highest medial arches (persistent cavovarus deformity).

CONCLUSION

This study reports minor, not statistically significant, changes of the ankle joint following triple arthrodesis after 7.5 years. Clinical outcome remained stable in time. Clinical relevance It seems that triple arthrodesis as such does not lead to major osteoarthritis of the ankle, given that adequate alignment of the hindfoot is achieved.

LEVEL OF EVIDENCE

Level II, retrospective study.

Assessment of plantar pressure in hindfoot relief shoes of different designs

BACKGROUND

Although there are several different concepts of hindfoot relief footwear, there are no studies on the extent of pressure reduction to be achieved by this footwear. Therefore, we sought to evaluate the reduction in plantar pressure to be achieved with two different hindfoot relief shoes.

METHODS

Ten healthy volunteers performed three trials at a self-selected speed. Peak pressure values in mass-produced shoes (normal gait) were considered as 100% and were compared with measurements in two differently designed hindfoot relief shoes. Foot portions were defined as heel (0%-15% of total insole length), hindfoot (16%-30%), midfoot (31%-60%), and forefoot (61%-100%).

RESULTS

Heel and hindfoot peak pressures were significantly reduced in both shoes compared with normal gait (P < .05), but the extent of peak pressure reduction under the heel and hindfoot varied significantly between the tested shoes. Midfoot peak pressure was not significantly reduced in tested shoes compared with baseline (P > .05) but differed significantly between the two shoes. Forefoot peak pressure was significantly reduced with one of the tested shoes (to a median 73% baseline; P = .004) but not with the other (median, 88% baseline).

CONCLUSIONS

Hindfoot relief shoes leave a considerable amount of peak pressure, predominantly under the hindfoot. The extent of peak pressure reduction for the heel and the hindfoot varies between different hindfoot relief shoes. Depending on the affected foot area, the kind of hindfoot relief shoe should be carefully chosen.

Pedobarography in the Assessment of Postoperative Calcaneal Fracture Pressure With Gait

The purpose of the present study was to evaluate the benefits and importance of pedobarography in the diagnosis and treatment of plantar pressure changes in the postoperative follow-up of calcaneus fractures treated with open reduction and internal fixation. The 28 patients included 23 males (82%) and 5 females (18%). The clinical evaluation was performed using the American Orthopaedic Foot and Ankle Society hindfoot scoring system. The Böhler and Gissane angles were measured on the preoperative and postoperative radiographs. In the postoperative follow-up period (mean ± standard deviation 22.25 ± 10.8 months), all the patients underwent analysis with a dynamic pedobarogram. Because the arch index of the operated feet was 29.73% and that of the nonoperated feet was 28.94%, a similar slightly low arch was seen in both feet (p = .078). When the plantar surface maximum pressures were evaluated, a significant reduction was seen in the operated feet in the second, third, fourth, and fifth metatarsals and the medial hindfoot (p < .05). Displaced intra-articular calcaneus fractures resulted in a significant reduction in maximum pressure of the second, third, fourth, and fifth metatarsals and the medial hindfoot. Also, the hindfoot pressure was lateralized. Pedobarography is a simple and useful method for the diagnosis of plantar pressure changes occurring postoperatively.

Mid- to long-term outcome of 96 corrective hindfoot fusions in 84 patients with rigid flatfoot deformity

Talonavicular and subtalar joint fusion through a medial incision (modified triple arthrodesis) has become an increasingly popular technique for treating symptomatic flatfoot deformity caused by posterior tibial tendon dysfunction. The purpose of this study was to look at its clinical and radiological mid- to long-term outcomes, including the rates of recurrent flatfoot deformity, nonunion and avascular necrosis of the dome of the talus. A total of 84 patients (96 feet) with a symptomatic rigid flatfoot deformity caused by posterior tibial tendon dysfunction were treated using a modified triple arthrodesis. The mean age of the patients was 66 years (35 to 85) and the mean follow-up was 4.7 years (1 to 8.3). Both clinical and radiological outcomes were analysed retrospectively. In 86 of the 95 feet (90.5%) for which radiographs were available, there was no loss of correction at final follow-up. In all, 14 feet (14.7%) needed secondary surgery, six for nonunion, two for avascular necrosis, five for progression of the flatfoot deformity and tibiotalar arthritis and one because of symptomatic overcorrection. The mean American Orthopaedic Foot and Ankle Society Hindfoot score (AOFAS score) at final follow-up was 67 (between 16 and 100) and the mean visual analogue score for pain 2.4 points (between 0 and 10). In conclusion, modified triple arthrodesis provides reliable correction of deformity and a good clinical outcome at mid- to long-term follow-up, with nonunion as the most frequent complication. Avascular necrosis of the talus is a rare but serious complication of this technique.

Incompliance of total hip arthroplasty (THA) patients to limited weight bearing

INTRODUCTION

Limited weight bearing of the lower extremity is a commonly applied procedure in orthopedic rehabilitation following trauma surgery and joint replacement. The compliance of patients with limited weight bearing after cementless total hip arthroplasty has not yet been surveyed using sensor-loaded insoles. The objective of this study was to investigate foot loadings in patients after THA under the assumption of limited weight bearing.

METHODS

Peak pressures for the hindfoot, midfoot and forefoot were obtained from 14 patients (10 women, 4 men, age 63 ± 12 years, height 172 ± 9 cm, weight 92 ± 20 kg, BMI 31 ± 6 kg/m(2)) by means of dynamic pedobarography, with full weight bearing preoperatively (baseline) and at 8-10 days after cementless total hip arthroplasty, walking again on even floor, and also walking upstairs and downstairs with a restriction of weight bearing to 10 % body weight, taught by an experienced physiotherapist with a bathroom scale.

RESULTS

Foot loadings with limited weight bearing on even floor remained up to 88 % from full weight bearing preoperatively. Walking upstairs and downstairs under the same condition was approximately equal to a bisection of peak pressures from full weight bearing.

CONCLUSIONS

Patients following cementless do not comply with limited weight bearing when they are trained by the use of a bathroom scale.

Single-incision lateral approach for triple arthrodesis

BACKGROUND

Triple arthrodesis is a powerful hindfoot corrective procedure involving fusion of the talonavicular (TN), calcaneocuboid (CC), and subtalar (ST) joints. A 2-incision approach, a single-incision medial triple arthrodesis, and a single-incision medial double arthrodesis are well described. We present a single-incision lateral approach to triple arthrodesis.

METHODS

We retrospectively reviewed 70 patients who underwent triple arthrodesis at our institution from 2007 to 2011. Patients had either double-incision (n = 33) or single-incision lateral (n = 37) triple arthrodesis. A single surgeon performed all procedures. The most common diagnosis was stage III planovalgus deformity. Deformity correction, union rate, time of surgery, complications, wound healing, reoperations, and pre- and postoperative visual analog scale (VAS) pain scores were analyzed for both groups.

RESULTS

There were no statistical differences in deformity correction, wound healing, complications, reoperations, or improvement in VAS pain scores. Operation time was significantly shorter in the single-incision lateral group (86 minutes vs 95 minutes, P = .0395). There was no difference in union rates with regard to the TN, ST, or CC joints. Five patients had radiographic nonunions of the CC joint between both groups.

CONCLUSIONS

This is the first study that presents outcomes of a single lateral approach for triple arthrodesis. The single-incision approach was faster. The low rate of symptomatic nonunions suggests that fusion of the CC joint may not be important in symptomatic relief or deformity correction.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Kinematic changes in patients with double arthrodesis of the hindfoot for realignment of planovalgus deformity

Double fusion (i.e., fusion of the subtalar and talonavicular joint) represents a modification of triple arthrodesis preserving integrity of the calcaneocuboidal joint. Our aims were (1) to evaluate dynamic plantar pressure distribution in patients undergoing double arthrodesis, (2) to obtain a comparison of kinematic changes to healthy feet, (3) to evaluate the influence of radiographic alignment, and (4) to assess functional outcome. Sixteen feet (14 patients) treated by double fusion due to fixed planovalgus deformity were included. Dynamic plantar pressure distribution was assessed using a capacitive pressure platform. Results were compared with a demographically matched control group. Clinical assessment included the American Orthopaedic Foot and Ankle Society (AOFAS) score and radiographic assessment included measurement of talometatarsal, calcaneal pitch, and talocalcaneal (TC) angle on lateral radiographs. Significant differences in plantar pressure distribution were found for maximum force of the hindfoot, midfoot, and big toe region: While the hindfoot and hallux represented decreased load in the double arthrodesis patients, load increased in the midfoot region compared with healthy controls. The lateral talus-first metatarsal-angle increased from -16.3° to -8.2°, and the TC angle decreased from 41.3° to 35.8° (p < 0.05). The pre- and post-operative AOFAS score increased from 37 points (SD, 16.3) to 70 points (SD, 16.7). These results revealed that double arthrodesis represents a reliable method for correction of planovalgus deformity. Compared with healthy feet, force transmission of the midfoot is increased whereas push-off force decreases.

Surgical treatment of hindfoot inflammatory diseases: 107 arthrodesis

INTRODUCTION

In rheumatoid diseases, hindfoot arthrodesis abolishes pain and corrects deformity. The choice between selective and double arthrodesis depends on whether the hindfoot malalignment is fixed or not. Indications for surgery are well codified. The various types of arthrodesis have never been assessed together on a large series. We here report a series that is substantial in numbers and in follow-up.

MATERIALS AND METHODS

A continuous single-center retrospective study included patients with native hindfoot inflammatory disease treated by arthrodesis between 1996 and 2009.

RESULTS

Around 80% of patients were followed up, for a mean 7 years. Fifty-four isolated talonavicular arthrodeses, 14 talocalcaneal arthrodeses and 39 double arthrodeses were performed. 96% of patients had rheumatoid arthritis and 4% spondylarthritis. 62% were completely pain-free at follow-up. The satisfaction rate was 91% and mean AOFAS score 70%. 6% of patients showed symptomatic non-union, mainly associated with talonavicular arthrodesis. In 22% of double arthrodeses and 11% of talonavicular arthrodeses, ankle status required surgical revision. In double arthrodesis, there was no correlation between hindfoot deviation and secondary deterioration in ankle status. Talocalcaneal arthrodesis was associated with radiologic hindfoot varus, both preoperatively and at follow-up.

DISCUSSION

Non-union was the main complication in talonavicular arthrodesis. The rate of secondary ankle surgery was significantly elevated in double arthrodesis. These findings support Suckel's cadaver studies, which, in 2007, reported early deterioration in ankle status in double arthrodesis, due to mechanical overloading. Talocalcaneal arthrodesis proved reliable and simple, free of major complications and with a 100% satisfaction rate.

CONCLUSION

Double arthrodesis showed the greatest benefit in terms of restoring foot architecture, but was associated with a higher rate of deterioration in ankle status. Preventive double arthrodesis is not recommended in case of isolated arthritis with reducible hindfoot malalignment.

Management of the rigid arthritic flatfoot in adults: triple arthrodesis

The traditional surgical treatment for adults with a rigid, arthritic flatfoot is a dual-incision triple arthrodesis. Over time, this procedure has proved to be reliable and reproducible in obtaining successful deformity correction through fusion and good clinical results. However, the traditional dual-incision triple arthrodesis is not without shortcomings. Early complications include lateral wound problems, malunion, and nonunion. Long-term follow-up of patients after a triple arthrodesis has shown that many develop adjacent joint arthritis at the ankle or midfoot. This particular problem should be considered an expected consequence, rather than a failure of the procedure. Although the indications for and surgical techniques used in triple arthrodesis have evolved and improved with time (predictably improving results in the intermediate term), the triple arthrodesis should be regarded as a salvage procedure. Certain measures can be taken by the surgeon to avoid some problems. If patients are at risk for lateral wound complications, the arthrodesis could be performed through a single medial incision. However, this can make some aspects of the CC fusion more difficult. Implants would have to be inserted percutaneously, which prevents the surgeon from using either staples or plates. If a patient were to need a lateral column lengthening through a CC distraction fusion, this would not be possible medially. If either the ST or CC joints have minimal degenerative changes, they could be spared through a double or modified double arthrodesis, respectively. Although these procedures that deviate from the traditional triple arthrodesis offer promise, further study is required to better define their role in treatment of the rigid, arthritic AAFD. Triple arthrodesis is, by no means, a simple surgery. It requires preoperative planning, meticulous preparation of bony surfaces, cognizance of hindfoot positioning, and rigidity of fixation. The procedure also requires enough experience on the part of the operating surgeon to anticipate postoperative problems and provide modifications in traditional technique for certain patients.

Foot loading with an ankle-foot orthosis: the accuracy of an integrated physical strain trainer

PURPOSE

To investigate the value of a built-in physical strain trainer for the monitoring of partial weight bearing with an ankle-foot orthosis.

METHODS

12 healthy volunteers were asked to perform three trials. Plantar peak pressure values from normal gait (trial one) were defined as 100% (baseline). The following trials were performed with the Vacoped® dynamic vacuum ankle orthosis worn in a neutral position with full weight bearing (trial two) and a restriction to 10% body weight (BW) (trial three), as monitored with an integrated physical strain trainer. Peak plantar pressure values were obtained using the pedar® X system.

RESULTS

Peak pressure values were statistically significantly reduced wearing the Vacoped® shoe with full weight bearing for the hindfoot to 68% of the baseline (normal gait) and for the midfoot and forefoot to 83% and 60%, respectively. Limited weight bearing with 10% BW as controlled by physical strain trainer further reduced plantar peak pressure values for the hindfoot to 19%, for the midfoot to 43% of the baseline and the forefoot to 22% of the baseline.

CONCLUSIONS

The Vacoped® vacuum ankle orthosis significantly reduces plantar peak pressure. The integrated physical strain trainer seems unsuitable to monitor a limitation to 10% BW adequately for the total foot. The concept of controlling partial weight bearing with the hindfoot-addressing device within the orthosis seems debatable but may be useful when the hindfoot in particular must be off-loaded.

Inaccuracy of a physical strain trainer for the monitoring of partial weight bearing

OBJECTIVE

To investigate the use of a physical strain trainer for the monitoring of partial weight bearing.

DESIGN

Case series with healthy volunteers.

SETTING

Orthopedic clinic.

PARTICIPANTS

Healthy volunteers (N=10) with no history of foot complaints.

INTERVENTIONS

Volunteers were taught to limit weight bearing to 10% body weight (BW) and 50% BW, monitored by a physical strain trainer.

MAIN OUTCOME MEASURES

The parameters peak pressure, maximum force, force-time integral, and pressure-time integral were assessed by dynamic pedobarography when volunteers walked with full BW (condition 1), 50% BW (condition 2), and 10% BW (condition 3).

RESULTS

With 10% BW (condition 3), forces with normative gait (condition 1) were statistically significantly reduced under the hindfoot where the physical strain trainer is placed. All pedobarographic parameters were, however, exceeded when the total foot was measured. A limitation to 10% BW with the physical strain trainer (condition 3) was equal to a bisection of peak pressure and maximum force for the total foot with normative gait (condition 1). Halved BW (condition 2) left a remaining mean 82% of peak pressure and mean 59% of maximum force from full BW (condition 1).

CONCLUSIONS

The concept of controlling partial weight bearing with the hindfoot-addressing device does not represent complete foot loading. Such devices may be preferably applied in cases when the hindfoot in particular must be off-loaded. Other training devices (eg, biofeedback soles) that monitor forces of the total foot have to be used to control partial weight bearing of the lower limb accurately.

Plantar pressure distribution after tibiotalar arthrodesis

INTRODUCTION

Arthrodesis is a well-established treatment option for end-stage osteoarthritis of the ankle. Osteoarthritis of the ankle can alter plantar pressure distribution. However, surprisingly little is known about the effect of ankle arthrodesis to alter plantar pressure distribution. The purpose of this study was to determine plantar pressure distribution in a selected group of patients with unilateral arthrodesis of the ankle joint.

METHODS

20 patients with an average age of 60 years who underwent isolated unilateral ankle arthrodesis using a 3-crossed screw technique by a single surgeon were included. After a mean of 25 months (range 12-75 months) post surgery plantar pressure distribution was determined in five regions of the foot. The outcome was evaluated clinically, using the American Orthopaedic Foot and Ankle Society hindfoot score, as well as radiographically. The contralateral normal foot was used as a control.

FINDINGS

Comparing the foot that underwent tibiotalar arthrodesis to the contralateral normal foot, differences were found in the peak pressure and maximum force in the toe region and the lateral midfoot region. In addition, a decrease in the contact time in the forefoot region and a decrease of the contact area in the toe region of the operated foot were identified. The other regions did not show a significant difference. The mean American Orthopaedic Foot and Ankle Society score of the operated leg was 79 (range 46-92) at the last follow up, and the mean fixation angle of the arthrodesis on lateral weight bearing radiographs was 90° (range 86°-100°).

INTERPRETATION

Our results indicate that arthrodesis of the ankle joint can provide high levels of function with minimal changes in the plantar pressure distribution.