Surgical treatment of osteochondral lesions of the talus.

When conservative treatment is unsuccessful, there are many surgical options to treat patients with symptomatic chronic osteochondral lesions of the talus. The chosen treatment depends on the patient's symptoms, clinical examination findings, preoperative imaging results, and whether prior surgery was unsuccessful. It is important to be aware of treatment alternatives such as marrow stimulation, osteochondral autograft or allograft plugs, autologous chondrocyte implantation, and newer techniques currently being investigated outside the United States.

Arthrodesis of the first metatarsocuneiform joint: a comparative study of fixation methods.

BACKGROUND: The Lapidus bunionectomy is a popular procedure for severe bunion deformity where metatarsus primus varus is equal to or exceeds 15 degrees. We evaluated a new locking compression plate which may improve outcomes with the Lapidus procedure. METHODS: Ten matched pairs of cadaver feet were used to compare the standard crossed 4.0-mm compression screw method of fixation to the LPS Lapidus plate. After performing the matched operations the cadaver constructs were stressed to failure using the INSTRON and Wavemaker software. RESULTS: The LPS Lapidus plate load to failure was 108 Nm with a bending moment of 6.0 Nm. The crossed screw technique was inferior at 78 Nm with a bending moment of 4.4 Nm (p = 0.02) CONCLUSION: Unlike other H-plates or locking plates, load to failure was higher with the Lapidus plate constructs. CLINICAL RELEVANCE: The increased rigidity provided by these plates may help to minimize the risk of nonunion or malunion.

Bone suture anchor fixation in the lower extremity: a review of insertion principles and a comparative biomechanical evaluation.

BACKGROUND: Suture anchors have been developed for the fixation of ligaments, capsules, or tendons to bone. These devices have led to improved fixation, smaller incisions, earlier limb mobility, and improved outcomes. They were originally developed for use in shoulder reconstructions but are now used in almost all extremities. In the lower leg they are used in the tibia, the talus, the calcaneus, tarsal bones, and phalanges. Nevertheless, techniques for insertion and mechanisms of failure are not well described. METHODS: Five suture anchors were studied to determine the pullout strength in four distal cadaver femurs and four proximal cadaver tibias from 55- and 62-year-old males. Eight hundred ninety Newton line was used, testing the anchors to failure with an Instron testing device (Instron, Norwood, MA). The anchor devices were inserted randomly and tested blindly (12 tests per anchor device, 60 tests in all). RESULTS: Two anchors in each group tested failed at low loads. Both types of plastic anchors had failures at the eyelet. Average pullout strength varied from 85.4 to 185.6 N. CONCLUSIONS: Insertion techniques are specific for each device, and they must be followed for optimal fixation. In this study, in all five groups of anchors tested two of the 12 anchors in each group failed with minimal force. On the basis of this finding we recommend that, if suture anchor fixation is necessary, at least two anchors should be used. Since there appears to be a percentage of failure in all devices, the second anchor can serve as a backup. It is imperative that surgeons be familiar with the insertion techniques of each device before use.

Variations in fibular position, talar length, and anterior talofibular ligament length.

BACKGROUND: Proprioceptive deficiencies, peroneal muscle weakness, varus hindfoot, and varus tibial plafond have each been implicated as a predisposing factor in recurrent ankle instability. Another predisposing factor for instability is a position of the fibula posterior to the transverse axis of the talus. This study examined the relationship of fibular position and ankle instability with anatomic dissection and magnetic resonance imaging (MRI). METHODS: Data were obtained from 100 consecutive MRI scans of adult ankles: the malleolar index in degrees and the fibular position anterior or posterior to the anteromedial malleolar plane and relative to the transverse axis of the talus. Twenty cadaver ankles also were studied by MRI and then by anatomic dissection. The malleolar index, the talar length, and the length of the anterior talofibular (ATF) ligament were recorded. RESULTS: The MRI study showed that variation of the malleolar index ranged from 2 to 30 degrees. There was no correlation between the malleolar index and the talar length or the length of the ATF ligament. CONCLUSIONS: There is a bell-shaped curve of variation of the position of the fibula relative to the transverse axis of the talus. An ankle mortise with a more posteriorly positioned fibula has less structural stability and is more susceptible to sprain. Neither talar length nor ATF ligament length correlated with fibular position.

Physiologic axial load, frictional resistance, and the football shoe-surface interface.

The purpose of this investigation was to report on the interaction between different types of athletic shoes and playing surfaces using physiologic loads of 40 and 220 lbs. This is a continuation of our previous report using a load of 25 lbs. Nine shoes by three manufacturers were characterized as turf, court, molded cleat, or traditional cleat and tested on both natural grass and synthetic turf. A specially designed pneumatic testing device was used in order to measure translational resistance and rotational torque of the shoe-surface interface. Measurements were acquired for 1) force-X describing translational loading, 2) moment-Y describing the torque generated by linear translation, and 3) moment-Z describing the moment generated by axial rotation, and data were analyzed using repeated measures analysis of variance and Tukey's post-hoc comparison. It was found that increased the axial loads from 40 to 220 lbs significantly increased the frictional resistance (p < .05) between the shoe and the artificial turf surface in a nonlinear fashion. Turf shoes demonstrated the most frictional resistance of any group for this condition. Increases in the forces generated in linear translation from the axial load of 40 to 220 lbs produced the most significant increases of any resistance test on the turf surface. The cleated shoes (both traditional and molded) generated the highest frictional and torsional resistance on the grass surface when compared to the other categories of shoes. Grass generated higher peak moments than turf for the cleated shoes. These results demonstrate the considerable differences between laboratory and physiologic conditions and that the increase in frictional resistance is nonlinear with increasing loads.

Osteochondral autologous transfer system.

The OATS technique is one of several cartilage repair procedures that exhibits promising short- to intermediate-term results in the surgical management of OLTs. Although the OATS procedure is generally reserved for salvage of failed debridement and drilling, some investigators are suggesting that it may have applications in primary surgical management of OLTs, particularly those that are associated with subchondral cysts. Long-term outcome of the OATS procedure for OLTs is not yet available.

Quadruple hamstring anterior cruciate ligament reconstruction: a multicenter study.

PURPOSE: The use of blunt-threaded titanium interference screws for arthroscopic-assisted fixation of a quadruple-strand hamstring anterior cruciate ligament (ACL) reconstruction has recently been reported. However, the pitfalls of the low medial portal technique, rehabilitation protocol, and long-term results have not. The purpose of this multicenter study was to prospectively evaluate this technique's application to ACL instability in symptomatic patients as well as to develop a standardized rehabilitation protocol. TYPE OF STUDY: Observation cohort study. METHODS: One hundred-twenty patients had quadruple hamstring ACL reconstructions, followed the study protocol, and were seen at 2 years follow-up. They were evaluated using Lysholm score, Lachman test, anterior drawer test, pivot-shift test, KT-1000, effusion assessment, and the Tegner Sports Activity Scale. RESULTS: The average Lysholm score improved 42 points; Lachman test, effusion assessment, anterior drawer test, KT-1000, and Tegner Sports Activity Scale scores all improved. Of 120 ACL reconstructions, 5 failed. Of these, 3 failed from new late injury, 1 from technical error, and 1 from patient nonadherence to rehabilitation protocol. Some anterior knee pain was present in 30% of patients, and 22% had at some time experienced hamstring pain that did not interfere with athletic activity. CONCLUSIONS: This multicenter study reports success with quadruple hamstring ACL reconstruction using the low medial portal technique. Specific pitfalls and a rehabilitation protocol are also discussed. Low medial portal position is critical in successful surgery. Variations in screw size to accommodate the variation in graft construct size are also recommended.

Use of bone graft substitutes in lower extremity reconstructive surgery.

Autologous iliac crest graft has been a standard source of supplementary bone for treating bony defects, fractures and arthrodeses. Bone graft substitutes have recently become widely available. This paper reports on the use of bone graft substitute in 28 patients that otherwise would have required an iliac crest graft. Twenty-four of the 28 operations were successful in the primary procedure with four patients requiring a second procedure that was then successful.