Christopher W. DiGiovanni

Isolated gastrocnemius tightness

Background: Contracture of the gastrocnemius-soleus complex has well-documented deleterious effects on lower-limb function in spastic or neurologically impaired individuals. There is scarce literature, however, on the existence of isolated gastrocnemius contracture or its impact in otherwise normal patients. We hypothesized that an inability to dorsiflex the ankle due to equinus contracture leads to increased pain in the forefoot and/or midfoot and therefore a population with such pain will have less maximum ankle dorsiflexion than controls. We further postulated that the difference would be present whether the knee was extended or flexed. Methods: This investigation was a prospective comparison of maximal ankle dorsiflexion, as a proxy for gastrocnemius tension, in response to a load applied to the undersurface of the foot in two healthy age, weight, and sex-matched groups. The patient group comprised thirty-four consecutive patients with a diagnosis of metatarsalgia or related midfoot and/or forefoot symptoms. The control group consisted of thirty-four individuals without foot or ankle symptoms. The participants were clinically examined for gastrocnemius and soleus contracture and were subsequently assessed for tightness with use of a specially designed electrogoniometer. Measurements were made both with the knee extended (the gastrocnemius under tension) and with the knee flexed (the gastrocnemius relaxed). Results: With the knee fully extended, the average maximal ankle dorsiflexion was 4.5° in the patient group and 13.1° in the control group (p < 0.001). With the knee flexed 90°, the average was 17.9° in the patient group and 22.3° in the control population (p = 0.09). When gastrocnemius contracture was defined as dorsiflexion of ⩽5° during knee extension, it was identified in 65% of the patients compared with 24% of the control population. However, when gastrocnemius contracture was defined as dorsiflexion of ⩽10°, it was present in 88% and 44%, respectively. When gastrocnemius-soleus contracture was defined as dorsiflexion of ⩽10° with the knee in 90° of flexion, it was identified in 29% of the patient group and 15% of the control group. Conclusions: On the average, patients with forefoot and/or midfoot symptoms had less maximum ankle dorsiflexion with the knee extended than did a control population without foot or ankle symptoms. When the knee was flexed 90° to relax the gastrocnemius, this difference was no longer present. Clinical Relevance: These findings support the existence of isolated gastrocnemius contracture in the development of forefoot and/or midfoot pathology in otherwise healthy people. These data may have implications for preventative and therapeutic care of patients with chronic foot problems.

Current concepts : Lateral ankle instability

Ankle sprains are the most common musculoskeletal injury, with an incidence of 30,000 per day in the United States;28,35 40% of all athletic injuries involve the ankle.12,28 Most ankle sprains involve the lateral ligament complex and are caused by an inversion force on a plantarflexed foot.42 In 1965, Freeman40 hypothesized that injury to the mechanoreceptors of the ankle joint was the main factor for continued symptoms after ankle sprain. Despite the large number of ankle sprains each year, however, most individuals do not develop chronic ankle instability. Those who do generally have two distinct presentations. Patients with mechanical instability complain of giving way and have documented pathologic hypermobility of the tibiotalar joint.28 Individuals with functional instability present with subjective complaints of an unreliable ankle but lack any demonstrable radiographic signs of instability.41 Significant research in recent years indicates that patients with either acute lateral ligament tears or chronic functional instability are best managed with a bracing and rehabilitation program, as substantiated by the 2002 Cochrane Database review by Kerkhoffs et al.75 Controversy still exists, however, regarding the optimal treatment of individuals with chronic mechanical ankle instability. What has become clear is that prevention of lateral ankle instability is mandatory, because the relationship between chronic instability and late sequelae, such as arthritic progression has become more obvious,54 although further Level I16,107 (Table 1) outcomes research are necessary to define these issues.

Arthroscopic evaluation of the subtalar joint: does sinus tarsi syndrome exist?

This is a retrospective review of 49 subtalar arthrosco-pies performed between 1989 and 1996. Patients were evaluated in the following areas: (1) preoperative diagnosis, (2) preoperative tests and clinical evaluation, (3) intraoperative findings, (4) postoperative diagnosis,(5) complications, and (6) clinical outcome. Particular attention was paid to the accuracy of the preoperative diagnosis, subtalar instability, intraoperative findings in sinus tarsi syndrome, and clinical outcome. Overall, this study demonstrated a success rate of 94% good and excellent results in the treatment of various types of subtalar pathologic conditions with arthroscopic techniques. The Workers’ Compensation cases reported 90% good and excellent results. The complication rate was low, with five minor complications reported. The most common complication was a transient neuropraxia involving branches of the superficial peroneal nerve. Of the 14 feet that had a preoperative diagnosis of sinus tarsi syndrome, all the diagnoses were changed at the time of arthroscopy. The postoperative diagnoses included 10 interosseous ligament tears, two cases of arthrofibrosis, and two degenerative joints. Based on these findings, “sinus tarsi syndrome” seems to be an inaccurate term that should be replaced with a specific diagnosis. Arthroscopy is the tool that will allow the orthopaedic surgeon to make a more accurate diagnosis.

Osteonecrosis in the Foot

Abstract Osteonecrosis, also referred to as avascular necrosis, refers to the death of cells within bone caused by a lack of circulation. It has been documented in bones throughout the body. In the foot, osteonecrosis is most commonly seen in the talus, the first and second metatarsals, and the navicular. Although uncommon, osteonecrosis has been documented in almost every bone of the foot and therefore should be considered in the differential diagnosis when evaluating both adult and pediatric foot pain. Osteonecrosis is associated with many foot problems, including fractures of the talar neck and navicular as well as Kohlers disease and Freibergs disease. Orthopaedists who manage foot disorders will at some point likely be faced with the challenges associated with patients with osteonecrosis of the foot. Because this disease can masquerade as many other pathologies, physicians should be aware of the etiology, presentation, and treatment options for osteonecrosis in the foot.

Flexor Hallucis Longus Transfer for Repair of Chronic Achilles Tendinopathy

Background: The flexor hallucis longus (FHL) tendon has been used to augment the repairs for chronic Achilles tendinopathy. Two common methods of FHL harvesting include a single incision (posterior) technique and a double incision (posterior and medial utility) technique. This cadaver study was designed to measure and compare the lengths of FHL tendon obtainable for reconstruction with each technique. Methods: Fourteen fresh-frozen cadaver lower limbs were utilized for FHL harvest. The tendon was first exposed through the single posterior-medial incision approach adjacent to the Achilles. A second medial utility midfoot incision was then made and the FHL was marked at the level of Henrys knot with a suture, to approximate the level of potential harvest via a two-incision technique. The FHL was then harvested and delivered into the posterior wound. Single incision technique graft length was then measured from the tip of the calcaneal tuber to the level of transection. The remaining in situ tendon was then also measured between its level of transection and the more distal suture placed at Henrys knot. These two lengths were then combined to determine the total potential tendon graft length obtainable using a double incision technique. Results: The average length of the FHL tendon harvested through the single posterior incision technique measured 5.16 cm (range, 3.4–6.9 cm, SD = 1.29). The average total tendon graft length available using the double incision technique measured 8.09 cm (range, 5.1–11.1 cm, SD = 1.63). The difference between the lengths obtained from these two techniques was significant (p < .001). Conclusions: These results demonstrate approximate FHL graft lengths obtainable by using either a single or double incision harvest technique and show that a significantly longer graft can be obtained using a double incision technique. Further data need to be obtained, however, to support whether the extra surgery and graft length obtained from a double incision technique are of any benefit in improving the ultimate functional outcome of these repairs.

Endoscopic gastrocnemius recession: evaluation in a cadaver model.

The purpose of this study was to describe a new method of gastrocnemius recession using an endoscopic approach and to determine the accuracy of incision placement during gastrocnemius recession. Fifteen fresh-frozen cadaveric limbs underwent an endoscopic gastrocnemius recession utilizing a two-portal technique. All limbs were anatomically dissected after the procedure and each was examined for injury to the sural nerve. The ability to visualize the sural nerve intraoperatively, improvement in ankle dorsiflexion, time requirement for the procedure, incision size, and appropriateness of placement to facilitate recession were recorded for each specimen. An average of 83% of the gastrocnemius aponeurosis was transected in all 15 cadavers. After modifications of the technique, the final eight cadavers were noted to have had the entire (100%) gastrocnemius aponeurosis transected. Sural nerve injury occurred in one specimen (7%) in which the aponeurosis and the sural nerve were not well visualized. The sural nerve was definitively visualized during the procedure in 5 of 15 specimens (33%). No Achilles tendon injury was noted in any specimen. There was a mean improvement in ankle dorsiflexion of 20° (range, 10°–30°) during full knee extension. The average length of time to perform the procedure was 20 minutes (range, 10–35 minutes). The average medial and lateral incision lengths used in the two-portal technique were 18 mm (range, 14–22 mm) and 17 mm (range, 12–19 mm), respectively, and the average distance from the midpoint of the medial incision to the level of the gastrocnemius-soleus junction was 26 mm (range, 5–60 mm). These results indicate that a complete gastrocnemius aponeurosis transection may be obtained utilizing a modified endoscopic gastrocnemius recession, but visualization of the sural nerve is poor with possible risk of iatrogenic nerve injury.

The safety and efficacy of intraoperative heparin in total hip arthroplasty.

A single dose of unfractionated heparin (15 U/kg), administered intravenously before surgery on the femur suppresses thrombogenesis during total hip replacement. Nine hundred eighty-nine patients (1021 hips) who received one dose of intraoperative heparin with hypotensive epidural anesthesia were followed up prospectively for 3 months. Asymptomatic deep vein thrombosis assessed by ultrasound in the first 198 consecutive patients showed an incidence of 7.1% (14 of 198). The incidence of clinical deep vein thrombosis in the subsequent 791 patients was 0.88% (seven of 791). Symptomatic pulmonary embolism occurred in 0.5% (five of 989). No patients died and there was one major bleeding episode. Based on this favorable experience, intraoperative heparin appears safe and efficacious as thromboembolic prophylaxis.

Recombinant Human Platelet-Derived Growth Factor-BB and Beta-Tricalcium Phosphate (rhPDGF-BB/β-TCP): An Alternative to Autogenous Bone Graft

BACKGROUND Joint arthrodesis employing autogenous bone graft (autograft) remains a mainstay in the treatment of many foot and ankle problems. However, graft harvest can lead to perioperative morbidity and increased cost. We tested the hypothesis that purified recombinant human platelet-derived growth factor-BB (rhPDGF-BB) homodimer combined with an osteoconductive matrix (beta-tricalcium phosphate [β-TCP]) would be a safe and effective alternative to autograft. METHODS A total of 434 patients were enrolled in thirty-seven clinical sites across North America in a prospective, randomized (2:1), controlled, non-inferiority clinical trial to compare the safety and efficacy of the combination rhPDGF-BB and β-TCP with those of autograft in patients requiring hindfoot or ankle arthrodesis. Radiographic, clinical, functional, and quality-of-life end points were assessed through fifty-two weeks postoperatively. RESULTS Two hundred and sixty patients (394 joints) underwent arthrodesis with use of rhPDGF-BB/β-TCP. One hundred and thirty-seven patients (203 joints) underwent arthrodesis with use of autograft. With regard to the primary end point, 159 patients (61.2% [262 joints (66.5%)]) in the rhPDGF-BB/β-TCP group and eighty-five patients (62.0% [127 joints (62.6%)]) in the autograft group were fused as determined by computed tomography at six months (p < 0.05). Clinically, 224 patients (86.2%) [348 joints (88.3%)]) in the rhPDGF-BB/β-TCP group were considered healed at fifty-two weeks, compared with 120 patients (87.6% [177 joints (87.2%)] in the autograft group (p = 0.008). Overall, fourteen of sixteen secondary end points at twenty-four weeks and fifteen of sixteen secondary end points at fifty-two weeks demonstrated statistical non-inferiority between the groups, and patients in the rhPDGF-BB/β-TCP group were found to have less pain and an improved safety profile. CONCLUSIONS In patients requiring hindfoot or ankle arthrodesis, treatment with rhPDGF-BB/β-TCP resulted in comparable fusion rates, less pain, and fewer side effects as compared with treatment with autograft.

Anatomic study of the gastrocnemius-soleus junction and its relationship to the sural nerve.

Background: Gastrocnemius recession is performed for equinus contracture of the ankle and as an adjunct treatment for various foot pathologies. Successful release relies on many factors, including a thorough knowledge of the anatomy of the gastrocnemius-soleus junction and its relationship to the sural nerve which may be vulnerable to iatrogenic injury. Neither the average width of the tendon at the gastrocnemius-soleus junction, the anatomy of the sural nerve with respect to the gastrocnemius-soleus junction, nor appropriate landmarks for accurate incision placement at this level to avoid undesirable vertical extension, however, have yet to be acceptably defined. Methods: Fourteen fresh-frozen cadavers were dissected and the width of the tendon at the gastrocnemius-soleus junction, the distance of the sural nerve from the lateral border of the tendon at this level, the length of the fibula, and the distance from the distal tip of the fibula to the gastrocnemius-soleus junction were measured. Results: The average width of the gastrocnemius-soleus complex at the junction was 58 mm (range, 44–69 mm), the average distance of the sural nerve from the lateral border of the gastrocnemius-soleus complex at the level of the gastrocnemius-soleus junction was 12 mm (range, 7–17 mm), the average percentage of this distance as compared to the entire width of gastrocnemius-soleus junction was 20% (range, 13%-27%), and the ratio of the distance of the gastrocnemius-soleus junction from the distal tip of the fibula divided by the length of the fibula was 0.5 (range, 0.5–0.6). Conclusion: These results provide some guidelines as to the approximate size of the gastrocnemius–soleus complex at the site of gastrocnemius recession along with the location of the sural nerve at the musculotendinous junction. Also, the results indicate that the fibula can serve as a reproducible anatomic landmark to enable localization of the gastrocnemius–soleus junction at the time of gastrocnemius recession.

Arthrodesis versus ORIF for Lisfranc fractures.

The Lisfranc joints make up the bony structural support of the transverse arch in the midfoot and account for approximately 0.2% of all fractures. Early recognition and treatment of this injury are paramount to preserving normal foot biomechanics and function. Controversy exists regarding the optimal treatment of patients with Lisfranc injuries, particularly when the instability is entirely ligamentous.The authors performed a qualitative, systematic review of the literature to compare the 2 most common procedures for Lisfranc fractures: primary arthrodesis and open reduction and internal fixation (ORIF). Six articles with a total of 193 patients met the inclusion criteria. At 1-year follow-up, the mean American Orthopaedic Foot and Ankle Society score of ORIF patients was 72.5 and of arthrodesis patients was 88.0. Fishers exact test revealed no significant effect of treatment group on the percentage on patients who had an anatomic reduction (P=.319).This study highlights that both procedures yield satisfactory and equivalent results. A slight advantage may exist in performing a primary arthrodesis for Lisfranc joint injuries in terms of clinical outcomes.