Paul Saluan

The porous-coated anatomic total hip prosthesis : Failure of the metal-backed acetabular component

One hundred and ninety-nine total hip arthroplasties were performed, between 1983 and 1987, in 173 patients by three surgeons using the initial design of the porous-coated anatomic prosthesis. The acetabular component was a preassembled, metal-backed polyethylene device, with beads sintered to the metal backing to allow bone ingrowth and two pegs for initial fixation. Twenty-three acetabular components (12 per cent) failed because of either migration or severe osteolysis. The radiographic appearance of osteolysis was positively associated with the duration that the implant had been in situ (p < 0.001). The prevalence of osteolysis was also significantly greater in acetabular components with an outer diameter of fifty-five millimeters or less (a polyethylene thickness of 8.5 millimeters or less) (p = 0.03). Thirteen hips were revised at a mean of 69.5 months (range, thirty-three to ninety-one months) after the index operation. Examination of the retrieved acetabular components revealed extensive polyethylene damage on the articular and back surfaces of the liners. Cracks in the polyethylene rim of the liner and deformation of the anti-rotation notch in the polyethylene rim were common findings. The density of the polyethylene was greater than expected, and more particles than anticipated had not fused with the surrounding polyethylene. The results of this study suggest that factors related to both the design and the material contributed to the failure of these porous-coated anatomic acetabular components. CLINICAL RELEVANCE: Patients who have had a total hip arthroplasty with the initial design of the porous-coated anatomic acetabular component should be closely monitored clinically for the onset of pain and radiographically for the development of osteolytic lesions or migration of the component. These findings are associated with impending failure of the component and may warrant revision of this portion of the hip replacement.

Anterior cruciate ligament injuries in the young athlete: evaluation and treatment.

Injuries to the pediatric and adolescent athlete are becoming more common as increasing numbers of this patient population are participating in year-round sporting activities. As these figures continue to rise, there have been an escalating number of patients with both traumatic and nontraumatic, sports-related knee injuries presenting to orthopedic surgeons for evaluation. Anterior cruciate ligament injuries in these patients, specifically in the skeletally immature, represent a complex problem. Treatment of these patients requires a thorough understanding of anatomy and physiology of the pediatric patient, the natural history of this injury, and knowledge of the potential complications of surgical intervention. This review will address these topics and will describe the presentation, diagnosis, and most commonly used surgical techniques currently being used with these patients. Future directions and advances in care of these injuries will also be discussed.

Mapping of cartilage depth in the knee and elbow for use in osteochondral autograft procedures.

Background: Osteochondritis dissecans (OCD) of the elbow is a problematic condition that affects a fair number of young athletes. One treatment option is the use of osteochondral autografts, which are commonly taken from donor sites on the less weightbearing surfaces of the knee. Purpose: To use magnetic resonance imaging (MRI) to assess the cartilage depths of sites in the knee and elbow that are commonly used as donor and recipient sites to optimize depth matching for osteochondral autograft procedures. Study Design: Descriptive laboratory study. Methods: All knee and elbow MRI scans acquired from 3-T machines in patients aged 16 to 25 years within a single hospital system were reviewed. Studies were excluded if there had been previous surgery on the joint or if there were significant chondral defects in the areas to be measured. All cartilage depth measurements were independently performed by 3 different physicians to the nearest 0.01 mm. At the elbow, 6 locations on the capitellum and 2 on the trochlea were chosen. At the knee, 4 locations along the anterior-lateral femoral condyle, 5 surrounding the intercondylar notch, and 1 on both the medial- and lateral-posterior femoral condyles were chosen. Results: There were 111 knee MRI (74 male, 37 female) and 94 elbow MRI (85 male, 9 female) scans that met all inclusion criteria. The average cartilage depths from each investigator were then averaged to provide an overall mean depth at each location. All average cartilage depths within the knee were thicker than those in the elbow, where the averaged mean thickness of all the 8 measured sites was 1.27 mm (range, 0.78-1.63 mm). Within the knee, the thinnest areas of cartilage, and therefore closest matches, were discovered at the posterior pole of the medial femoral condyle (mean ± SD, 1.95 ± 0.46 mm) and at the distal-most anterior-lateral femoral condyle (1.85 ± 0.46 mm). The average variance between the mean cartilage depths measured by each investigator for each location was 0.12 mm in the elbow and 0.22 mm in the knee. Conclusion: Average cartilage depths in the knee were thicker than those in the elbow at all sites measured. The thinnest areas in the knee were the posterior aspect of the medial femoral condyle and the distal-most aspect of the anterior-lateral femoral condyle. Clinical Relevance: This study provides the surgeon with meaningful data on average cartilage depths at common donor sites in the knee and recipient sites in the elbow.

Osteochondritis Dissecans of the Humeral Capitellum The Significance of Lesion Location

Background: There is a paucity of information regarding the effect of lesion location on surgical outcomes in the treatment of osteochondritis dissecans (OCD) of the humeral capitellum. Purpose: To survey the literature for conclusions that can be drawn regarding the effect of lesion location on treatment of capitellar OCD lesion. The hypothesis was that lesion severity and the need for more aggressive surgical interventions are increased for lesions that are located laterally on the capitellum. Study Design: Systematic review; Level of evidence, 4. Methods: All studies from the past 20 years were determined using a literature search of PubMed, Scopus, and Cochrane databases. Included studies were clinical studies that specifically commented on the location of the OCD defect on the capitellum. Excluded studies were case reports, review articles, and those that did not include information regarding the location of the OCD lesion on the capitellum. Results: Six studies met the inclusion criteria. Autograft reconstruction was found to yield reliable outcomes regardless of lesion location, as 87% (26/30) of lateral lesions had excellent or good outcomes using the Timmerman and Andrews score, while 91% (21/23) of central lesions had excellent or good outcomes. There was a trend toward improved outcomes with more aggressive surgical management of lateral lesions, specifically those involving the lateral cartilage margin. The failure rate for nonreconstructive operative management for lateral lesions was noted to be significant, as failure rates for peg fixation of lateral lesions was seen to be as high as 44% (4/9) in one of the studies. Conclusion: Studies regarding capitellar OCD lesion location, as it relates to symptom severity and surgical outcome, are limited. The literature suggests that lesions located on the lateral capitellum—particularly those involving the lateral cartilage margin—require more aggressive surgical management than those located medially. A refinement of the Takahara classification is proposed, which includes lesion location as a factor influencing surgical decision making.

Accuracy of 3-Tesla magnetic resonance imaging for the diagnosis of intra-articular knee injuries in children and teenagers.

Background: Magnetic resonance imaging (MRI) is a commonly used tool for the diagnosis of intra-articular knee pathologies. Although many studies have reported the accuracy of MRI in the adult population, fewer studies have investigated these tests in younger patients. Furthermore, these studies have shown a higher variability in both the sensitivity and the specificity of MRI for these knee injuries in this age group. Advancements in MRI technology, such as the 3-Tesla (3T) MRI magnet, have shown promising results for musculoskeletal injury diagnosis in adults. This study aims to evaluate 3 T MRI for the diagnosis of intra-articular knee pathologies in a pediatric and adolescent patient population. Methods: The records of 116 patients (119 knees) under the age of 20 years who underwent 3 T MRI studies of the knee and subsequent knee arthroscopy were reviewed retrospectively. The MRI report from the musculoskeletal radiology staff, the interpretation from the staff orthopedic surgeon, and the operative note dictations were compared, with a focus on meniscus and anterior cruciate ligament (ACL) pathologies. Seventeen orthopedic staff reads were not obtainable. Arthroscopy was used as the gold standard for diagnosis. Results: The average age at MRI exam was 16.0 years and at surgery was 16.2 years. Using the musculoskeletal radiologist interpretation, the sensitivity and the specificity of 3 T MRI were 81.0% and 90.9% for medial meniscus injuries, 68.8% and 93% for lateral meniscus injuries, and 97.9% and 98.6% for ACL injuries, respectively. The orthopedic surgeon’s interpretation of 3 T MRI had a sensitivity and specificity of 75.7% and 92.4% for medial meniscus injuries, 69.8% and 98.3% for lateral meniscus injuries, and 100% and 98.6% for ACL injuries, respectively. Posterior horn tears had the greatest discrepancies. Conclusions: When performed on pediatric and adolescent patients, newer 3 T MRI studies have excellent accuracy for diagnosing ACL tears. These studies also show a higher accuracy for the diagnosis of medial meniscal tears than lateral meniscal tears. Level of Evidence: Diagnostic study—Level 2.

Statistical Comparison of the Pediatric Versus Adult IKDC Subjective Knee Evaluation Form in Adolescents

Background: The International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form is a patient-reported outcome with adult (1998) and pediatric (2011) versions validated at different ages. Prior longitudinal studies of patients aged 13 to 17 years who tore their anterior cruciate ligament (ACL) have used the only available adult IKDC, whereas currently the pediatric IKDC is the accepted form of choice. Purpose/Hypothesis: This study compared the adult and pediatric IKDC forms and tested whether the differences were clinically significant. The hypothesis was that the pediatric and adult IKDC questionnaires would show no clinically significant differences in score when completed by patients aged 13 to 17 years. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: A total of 100 participants aged 13 to 17 years with knee injuries were split into 2 groups by use of simple randomization. One group answered the adult IKDC form first and then the pediatric form. The second group answered the pediatric IKDC form first and then the adult form. A 10-minute break was given between form administrations to prevent rote repetition of answers. Study design was based on established methods to compare 2 forms of patient-reported outcomes. A 5-point threshold for clinical significance was set below previously published minimum clinically important differences for the adult IKDC. Paired t tests were used to test both differences and equivalence between scores. By ordinary least-squares models, scores were modeled to predict adult scores given certain pediatric scores and vice versa. Results: Comparison between adult and pediatric IKDC scores showed a statistically significant difference of 1.5 points; however, the 95% CI (0.3-2.6) fell below the threshold of 5 points set for clinical significance. Further equivalence testing showed the 95% CI (0.5-2.4) between adult and pediatric scores being within the defined 5-point equivalence region. The scores were highly correlated, with a linear relationship (R2 = 92%). Conclusion: There was no clinically significant difference between the pediatric and adult IKDC form scores in adolescents aged 13 to 17 years. This result allows use of whichever form is most practical for long-term tracking of patients. A simple linear equation can convert one form into the other. If the adult questionnaire is used at this age, it can be consistently used during follow-up.

Anterior Cruciate Ligament Reconstruction Using a Flexible Reamer System Technique and Pitfalls

Anatomic reconstruction of the anterior cruciate ligament (ACL) has been shown to improve stability of the knee, particularly rotational stability, potentially leading to superior clinical outcomes and a shorter return to sport. Nonanatomic ACL reconstruction has been linked to graft failure and abnormal cartilage loading thought to contribute to progression of degenerative joint disease. Use of the far anteromedial portal (FAMP) to uncouple the tibial and femoral tunnels has led to improved reproduction of the femoral footprint and facilitates drilling of the femoral tunnel in an anatomic position. The use of the FAMP and straight reamer systems introduces its own set of potential complications, including short femoral tunnels and peroneal nerve injury. These potential complications have been addressed by drilling the femoral tunnel in a hyperflexed position, which can lead to difficulty with positioning the operative extremity, visualization, and identification of anatomic landmarks. The purpose of this case report was to review the advantages and technical aspects of using a flexible reamer system and the FAMP to achieve an anatomic ACL reconstruction while avoiding potential complications and pitfalls. Flexible reamer systems allow an additional way of uncoupling the tibial and femoral tunnels to clearly visualize and establish an anatomic starting point within the femoral footprint of the native ACL while avoiding the complications associated with knee hyperflexion and straight reamers with the far anteromedial portal. In the authors’ experience, an anatomic reconstruction of the ACL can be achieved safely using flexible reamers while avoiding some of the difficulties seen with straight reamers used in conjunction with an uncoupled, far anteromedial approach.

Outcomes After Arthroscopic Bankart Repair: Patients With First-Time Versus Recurrent Dislocations.

Background: The young athletic population makes up the largest portion of shoulder instability and, when treated nonoperatively, has a recurrent dislocation rate as high as 71%. It is unknown how the outcomes of those who have a recurrent dislocation are affected versus those who have a stabilization procedure after a first-time dislocation. Purpose: To report the postoperative outcomes of patients with first-time dislocations versus patients with recurrent dislocations before surgery. Study Design: Cohort study; Level of evidence, 3. Methods: Current Procedural Terminology codes were used to identify patients who had arthroscopic Bankart repair between 2003 and 2013. A total of 173 eligible patients were identified across 8 fellowship-trained surgical practices. The first phase of the study was a retrospective chart review. Patients were identified as having a first-time dislocation or as having recurrent dislocations when they had >1 dislocation before surgical intervention. The second phase consisted of a survey to record a Simple Shoulder Test score and return to sport and to report postoperative instability and whether patients had further surgery on the shoulder. Results: A total of 121 patients participated, providing 70% follow-up at an average of 51 months. There were 53 patients in the recurrent dislocation group and 68 in the first-time dislocation group. The postoperative instability rate was 29% in the first-time dislocation group and 62% in the recurrent dislocation group; this difference was significant (P < .001). The odds of postoperative instability were 4 times higher in the recurrent dislocation group (odds ratio = 4.14). The first-time dislocation group reported a 7% rate of repeat operation to address instability, whereas the recurrent dislocation group reported a rate of 32%; this difference was significant (P < .001). The odds of needing additional surgery on the index shoulder was 6 times higher in the recurrent dislocation group (odds ratio = 6.01). Conclusion: Patients with first-time dislocations had lower postoperative instability rates and reoperation rates when compared with patients with recurrent dislocations before surgery. Young patients with shoulder instability should be offered early surgical intervention to lower the risk of postoperative instability and reoperation.

Injury Types and Incidence Rates in Precollegiate Female Gymnasts: A 21-Year Experience at a Single Training Facility

Background: With childhood sports opportunities continuing to increase at an enormous rate along with participation starting at younger ages, the number of female participants in sports has increased in paramount fashion over the past few decades. A review of the current literature reveals a very small number of studies (<30) that document specific injuries suffered by competitive female gymnasts. Purpose: To retrospectively evaluate the incidence of various injuries and injury rates for different gymnast levels among young precollegiate female gymnasts over a 21-year period, from 1985 to 2005. Study Design: Descriptive epidemiological study. Methods: This institutional review board–approved study retrospectively evaluated young, precollegiate female gymnasts over a 21-year period. Gymnasts were stratified into 1 of 4 competition levels based on the number of hours spent training. In addition to the frequency of injuries and hours trained, data collected on each gymnast included the following: age at the time of injury, body part injured, laterality of the injury, and diagnosis. Results: Over the 21-year period, 3681 new injuries were evaluated by a single physician. The injury incidence (2.155 per 1000 exposure hours) was slightly lower when compared with previously reported injury rates. There were 1,452,574 total exposure hours documented from training facility records. The injury rate per 1000 exposure hours was 2.859 for elite, 2.820 for high-level, 1.667 for intermediate, and 0.687 for novice gymnasts. The lower extremity was injured more often than the upper extremity (60.9% compared with 22.6% of total injuries). This difference was statistically significant across all levels. Conclusion: The injury incidence in this study was 2.155 per 1000 exposure hours. This was slightly lower when compared with previously reported injury rates. Although those studies only lasted 3 years or less, the injury rates can be directly compared because they are reported as injuries per 1000 training hours. Clinical Relevance: With the variability in data available and limited studies reported, a conclusive analysis is needed because of the long-term effects of injury seen on gymnasts, such as early degenerative disorders, cost of injury treatment, and reduction of well-being. In our 21-year study, we found the incidence of injury was slightly lower than that shown in prior shorter studies. In addition, we were able to evaluate specific injuries seen in this population over that time period. Also, this extended study revealed the longitudinal nature of a series of injuries over a period of time that has not been seen in other studies, thus giving insight into the effects of increased gymnastics in the young, female, adolescent population, which could be potentially used in guidelines for gymnasts in the future.

No Clinically Significant Difference Between Adult and Pediatric IKDC Subjective Knee Evaluation Scores in Adults

Background: Two versions of the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation form currently exist: the original version (1999) and a recently modified pediatric-specific version (2011). Comparison of the pediatric IKDC with the adult version in the adult population may reveal that either version could be used longitudinally. Hypothesis: We hypothesize that the scores for the adult IKDC and pediatric IKDC will not be clinically different among adult patients aged 18 to 50 years. Study Design: Randomized crossover study design. Level of Evidence: Level 2. Methods: The study consisted of 100 participants, aged 18 to 50 years, who presented to orthopaedic outpatient clinics with knee problems. All participants completed both adult and pediatric versions of the IKDC in random order with a 10-minute break in between. We used a paired t test to test for a difference between the scores and a Welch’s 2-sample t test to test for equivalence. A least-squares regression model was used to model adult scores as a function of pediatric scores, and vice versa. Results: A paired t test revealed a statistically significant 1.6-point difference between the mean adult and pediatric scores. However, the 95% confidence interval (0.54-2.66) for this difference did not exceed our a priori threshold of 5 points, indicating that this difference was not clinically important. Equivalence testing with an equivalence region of 5 points further supported this finding. The adult and pediatric scores had a linear relationship and were highly correlated with an R2 of 92.6%. Conclusion: There is no clinically relevant difference between the scores of the adult and pediatric IKDC forms in adults, aged 18 to 50 years, with knee conditions. Clinical Relevance: Either form, adult or pediatric, of the IKDC can be used in this population for longitudinal studies. If the pediatric version is administered in adolescence, it can be used for follow-up into adulthood.