Variables affecting patellar height in patients undergoing primary total knee replacement.

BACKGROUND: Alteration of patellar height is commonly encountered in total knee arthroplasty (TKA), and failure to address patella baja can result in suboptimal functional outcomes. It may therefore be prudent to evaluate pre-operative patellar height (PPH) and to seek risk factors for patella baja. METHODS: Two hundred eighty-five patients who underwent TKA were included. Patient's age, gender, body mass index (BMI), and history of prior arthroscopy were recorded. PPH was measured using plateau-patella angle (PPA) as well as the Blackburn-Peel (BP), Caton-Deschamps (CD), and Insall-Salvati (IS) ratios. RESULTS: The average patients' age was 71 years with a mean BMI of 30.45. There were 191 female and 94 male patients. One-fourth of the cases had at least one prior knee arthroscopy. Multivariate linear regression analysis identified gender and BMI as variables significantly affecting the IS ratio (p: < 0.05). Gender also had a significant correlation with PPA. Male patients were likely to have lower PPA (p: < 0.03). Though increasing age had a positive correlation with patellar height, this was not statistically significant. History of prior arthroscopy had no significant effect on any of the four PPH measurements. CONCLUSION: Lower patellar height is significantly correlated to male gender and high BMI. We suggest that obese male patients be screened for pre-operative patella baja. This can help in surgical planning and optimizing results in TKA.

Primary Repair of Tibial-Sided Avulsion of the Anterior Cruciate Ligament.

Lesions of the anterior cruciate ligament (ACL) are common; the current gold standard of treatment for such lesions is ACL reconstruction. Tibial-sided soft-tissue avulsion is a rare subtype of ACL injuries. Unlike femoral-sided ACL repair, surgery for acute tibial-sided ACL ruptures has been neither reported nor described. This technical note presents a method for primary anatomic ACL reinsertion for an acute distal soft-tissue avulsion-type ACL injury, using a transosseous pull-out repair technique. Our technique, as an alternative to reconstruction, has the potential to enhance healing due to marrow stimulation (tibial tunneling). It also preserves the native insertion site and proprioceptive function, which may, in turn, reduce the risk of post-traumatic osteoarthritis.