[Clinical and computed tomography results of 106 Latarjet-Patte procedures at mean 7.5 year follow-up].

PURPOSE OF THE STUDY

We reviewed, at a mean follow-up of 7.5 years, overall functional outcome, bony architecture of the humerus predisposing to anterior instability, and treatment failure after 106 Latarjet-Patte procedures performed in 102 patients (mean age 34 years).

MATERIAL AND METHODS

The reproducibility of computed tomographic findings was validated prior to analysis. There were 5 men for 1 woman in this series. The initial injury, occurring at the age of 22 years on the average, was caused by trauma in 87% of the patients and generally involved the dominant upper limb. Ninety-seven patients practiced sports activities, a high risk sport for 48%. Clinical outcome was assessed with the Duplay score. Standard x-rays were also obtained, with bilateral computed tomography in 80 patients.

RESULTS

The osteosynthesis screw had to be removed in 6% of the cases due to posterior pain. The Latarjet-Patte procedure yielded 76.4% excellent or good results according to the Duplay scoring system. Sixty percent of the competition-level athletes like amateur athletes resumed their former sports activities at the same level. Seventy-percent of the patients were pain free. At last follow-up, complaints of pain, generally minor pain, were related to age of onset of instability, preoperative pain, and presence of joint degeneration. Loss of rotation was less than 11 degrees (mean). There was one case of recurrence subsequent to secondary trauma and 13.2% of the patients experienced residual apprehension. This lack of perfect stability was not related to a technical error but rather to a functional section of the head cartilage which remained in an overly anterior position because of a Malgaigne notch extending to the surface. Grade 2 or 3 joint degeneration was observed in 15% of the patients. It was related to duration of follow-up, patient age, mode of instability, and overlap of the bone block. Standard x-rays underestimated the incidence and degree of joint degeneration since the computed tomographic analysis revealed 17.5% of joint space narrowing (overall or posterior). Single cortex screwing led to nonunion, observed in 7% of the cases. Advanced osteolysis led to pain with altered overall function.

DISCUSSION

Operated patients appear to have a constitutional morphology predisposing to anterior instability due to more marked bicipital lateralization than seen in controls. The differences concerning humeral version are less pronounced. There was a difference in version, independently of the presence of a notch, between the unstable and the healthy side. Conversely, in comparison with controls, a more anterior sector of the head cartilage (secondary anteversion) was only seen in patients with a notch.

CONCLUSION

We consider that preoperative measurement of humeral retroversion and lateralization of the bicipital gutter can be helpful in establishing a precise therapeutic indication. Rather than searching for a constitutionally anomalous retroversion, we advocate searching for a more anterior functional section of the head cartilage (aggravated anteversion) caused by the presence of a Malgaigne notch on the unstable side (retroversion< or =0 degrees ). When this anomaly is present, we prefer associating a derotation retroversing osteotomy of the humerus with the classical technique. This should avoid persistent residual apprehension.