OKOJ, Volume 10, No. 7

Kinematic Alignment in Total Knee Arthroplasty: Definition, Surgical Technique, and Challenging Cases

Mechanically aligned total knee arthroplasty (TKA) improves the quality of life of patients with knee arthritis; however, studies have shown that 10% to 20% of patients are dissatisfied with their results. Accordingly, kinematically aligned TKA was implemented in 2006 as an alternative alignment strategy, with the goal of reducing the prevalence of unexplained pain, stiffness, and instability, and improving the rate of recovery, kinematics, and contact forces. In this article, we review the history and principles of kinematically aligned TKA, and describe in detail the technique for performing a kinematically aligned TKA with modified conventional instruments and the use of simple intraoperative checkpoints to confirm correct component position prior to cementation. Case studies of challenging deformities treated with kinematically aligned TKA are also presented. Although the short-term results of kinematically aligned TKA have been promising, longer-term survivorship remains to be demonstrated.

    • Keywords:
    • total knee replacement

    • total knee arthroplasty

    • knee replacement

    • knee arthroplasty

    • TKR

    • TKA

    • mechanical alignment

    • kinematic alignment

    • kinematics

    • osteoarthritis

    • mechanically aligned TKA

    • kinematically aligned TKA

    • Subspecialty:
    • Adult Reconstruction

Traumatic Injuries of the Adult Brachial Plexus

The increasing frequency and often devastating outcomes of traumatic injuries of the brachial plexus in adults make an understanding of these injuries important, and the orthopaedic surgeon should be familiar with their pathoanatomy and diagnostic evaluation. Such injuries may be successfully treatable through advances in microsurgical techniques, including nerve grafting, nerve transfer, and free muscle transfer, for the restoration of shoulder and elbow function as well as manual prehension.

    • Keywords:
    • brachial plexus injury

    • brachial plexus palsy

    • nerve root avulsion

    • brachial plexus avulsion injury

    • preganglionic nerve injury

    • postganglionic nerve injury

    • neurapraxia

    • neurotmesis

    • axonotmesis

    • electromyography

    • nerve conduction velocity studies

    • free-functioning muscle transfer

    • nerve transfer

    • tendon transfer

    • Subspecialty:
    • Hand and Wrist

    • Trauma

Proximal Humerus Fractures in the Elderly: Repair, Replace, or Reverse?

Displaced fractures of the proximal humerus in elderly patients continue to represent a challenge in orthopaedics. In addition to the complex geometry and multiple muscle forces acting across the glenohumeral joint, problems with bone healing due to comminution and/or poor bone quality, particularly with regard to fixation of the greater tuberosity, often add to the difficulties associated with treatment of these fractures in this patient population. Though nonsurgical treatment can be employed in most fractures of the proximal humerus, surgical intervention is recommended for widely displaced fractures. Four general methods of surgical treatment are currently in use: closed reduction and percutaneous pinning, open reduction and internal fixation, hemiarthroplasty, and reverse total shoulder arthroplasty. In this article, we discuss the relative merits and indications, surgical techniques, and outcomes for each of these interventions.

    • Keywords:
    • proximal humeral fracture

    • minimally invasive treatment

    • percutaneous pinning

    • hemiarthroplasty

    • reverse total shoulder arthroplasty

    • reverse TSA

    • reverse shoulder arthroplasty

    • locked plating

    • osteoporotic bone

    • osteoporosis

    • Subspecialty:
    • Shoulder and Elbow

HOT TOPIC: Update on the Management of Nonunion

A fracture nonunion represents a disturbance of the bone healing process. Nonsurgical treatment options for nonunion include nutritional enhancements, bracing, correction of endocrinopathy or metabolic disorder, and electromagnetic and ultrasonic bone stimulation. Surgical options include internal fixation, bone grafting, osteotomy, and distraction osteogenesis/bone transport. Amputation may also be considered for recalcitrant nonunions that have failed multiple operations designed to heal the bone, and are surrounded by a deficient soft-tissue envelope. Appropriate treatment is based on the type of nonunion and its anatomic location, because that will aid in the analysis of why the bone failed to heal and what it may need to achieve union. This article is an update on a previously published OKO topic on nonunion, with particular focus on diagnostic and nonsurgical therapeutic interventions and some new developments in surgical management.

    • Keywords:
    • fracture nonunion

    • ununited fracture

    • hypertrophic nonunion

    • atrophic nonunion

    • infected nonunion

    • synovial pseudarthrosis

    • nonsurgical management

    • electrical bone stimulation

    • electromagnetic bone stimulation

    • extracorporeal shock wave therapy

    • ultrasonic bone stimulation

    • bracing

    • bone marrow injection

    • surgical management

    • bone grafting

    • growth factors

    • Subspecialty:
    • Trauma