Patellar osteochondral fracture: The unforeseen hazard of golf CHRISTOPHER L. ISAACS,* DO, AND FREDERICK C. SCHREIBER, DO From the
Department of Orthopaedic Surgery,
Dislocation of the patella is a common disorder of the knee joint. It is seen most frequently in the adolescent female population.’ Osteochondral fractures complicate approximately 5% of all acute patellar dislocations.’ This fracture will usually occur at the medial side of the patella or, more seldomly, on the lateral margin or the lateral femoral condyle.4,5.8 This case report documents a unique presentation of a first-time patellar dislocation in an adult man during a golfing outing.
Osteopathic Hospital, Flint, Michigan
he was unable to actively extend his knee. However, if passively extended, he could maintain the position. ThighB atrophy was noted again, but quadriceps function was felt to be intact, with 4+ strength measurement. In the supine position the patient demonstrated apprehension with laterally directed pressure of the patella, but no obvious patellofemoral laxity was appreciated. There was mild synovitis of the knee, but no effusion identified. Neither joint line tenderness nor lateral femoral condyle discomfort was identified. With passive flexion and extension of the knee there was patellofemoral crepitus and pain. Ligaments were found to be unaffected; the Lachman and McMurray maneuvers were negative. The left lower extremity examination was unremarkable. The alignment was similar to that of the right, also with a Q angle of 9°. The left patella was found to be well seated in the trochlear groove with no apparent laxity or tendency
CASE REPORT A 36-year-old man presented for orthopaedic consultation 6 weeks after the onset of pain in his right knee. He originally sustained injury while playing golf. During the followthrough phase of his swing after a drive, he felt a &dquo;snap&dquo; within his right knee. He was unable to continue playing, although he could ambulate independently. He sought medical attention at a local emergency department where radiographic examination proved negative. It was recommended that he use crutches and he was placed in a knee immobilizer. Seven days later he discontinued use of the crutches, and at 14 days after injury he stopped using the knee immobilizer. However, he continued to have anterior right knee pain and was unable to actively extend his right knee. His functional impairment was a restricted ability to negotiate stairs. Because of these complaints and continued swelling he sought further medical attention. Physical examination revealed a cooperative patient who was 5 feet, 10 inches tall and weighed 160 pounds. He ambulated with a slight limp and favored his right leg. There was moderate thigh atrophy on the right side when the patient was in the standing position. The alignment of the involved extremity was otherwise within normal limits, with a Q angle of 9°. A particularly unusual finding was that when the patient was examined in the sitting position, with the knee flexed, * Address correspondence and reprint requests to: 9141 Grant Street, Suite 10, Thornton, CO 80229.
Flint
toward subluxation
or
dislocation.
Radiographs from the original emergency department visit were reviewed and found to be unremarkable. Repeat radiographs demonstrated bony fragments in the suprapatellar pouch region, which were seen in the lateral view (Fig. 1). Based on the patient’s history and physical findings, it was recommended that he undergo arthroscopic surgery. During surgery, the menisci, cruciate ligaments, and tibial articular surface were found to be within normal limits. Inspection of the lateral femoral condyle demonstrated an irregularity consistent with healing of a bony defect and cartilaginous injury along the middle arc region of the lateral aspect of the lateral femoral condyle. Visualization of the patellofemoral compartment revealed that the entire patellar articular surface had been avulsed. This damage was obviously full-thickness in nature. New fibrocartilaginous tissue was noted to have completely covered the defect. Further inspection of the suprapatellar pouch revealed a large osseous cartilaginous body scarred down to the anterior aspect of the femur just above the trochlear groove. This fragment was mobilized and removed. It measured 2.5 x 3.0 x 0.5 cm. The size of the fragment and its contour were consistent with the large patellar defect.
Christopher Isaacs, DO, 613
614
DISCUSSION
Figure 1. Lateral radiograph demonstrating bony fragment (arrow) in the suprapatellar region. At 2 weeks after surgery, the patient reported improvement in tenderness and function. Examination revealed soft tissue swelling and effusion. Range of motion of the knee was 0° to 90°. Straight leg raising, hip abduction, and range of motion exercises were instituted, along with ice massage. At 4 weeks he continued to show improvement. However, a 1+ effusion (on a scale of 1 to 4) had persisted. The patient demonstrated full extension against gravity with minimal discomfort and crepitus. Progressive resistance straight leg raising exercises were instituted along with the use of an exercise bike. At 10 weeks the patient demonstrated full range of motion. No synovitis or effusion was appreciated; quadriceps tone and bulk showed improvement. He was given a prescription for a patella stabilizing brace and allowed to return to full
activity.
Dislocation of the patella is usually the result of indirect trauma. The most common mechanism of injury is forced inward rotation of the femur against a fixed externally rotated tibia in combination with contraction of the quadriceps mechanism.l.2. 7.8 Osteochondral fracture of the patella or the femoral condyle, or both, occurs as the patella slides tangentially over the surface of the lateral femoral condyle with the knee in the flexed position.l.4-6,8 In the case presented here, the patient was able to accurately describe the mechanism of injury. It would at first seem most unusual for this injury to occur during the action of swinging a golf club. However, it can be biomechanically visualized that the follow-through phase of the stroke would involve internal rotation of the femur on a tibia fixed by a cleated golf shoe, with the knee in a partially flexed position. It must be reemphasized that this injury was unusual in that it was a first-time dislocation in an adult man in a nontraumatic situation.l°2 In addition, the presentation of a patient with loss of active extension with no disruption of the quadriceps mechanism has not been reported previously. We believe this loss of ability to extend the knee was secondary to impingement of the osteochondral fragment embedded in the synovium on the anterior femur. At the time of arthroscopic surgery, the femoral condyle injury was seen to have already begun healing. The large defect of the articular surface of the patella was covered with fibrocartilage. Removal of the large osteochondral fragment and other debris eliminated a significant portion of the patient’s discomfort and allowed for his rehabilitation.’ Had we been able to examine the injury soon after it occurred, fixation of an osteochondral fragment of this size might have been possible.3.8 As it was, this patient had successful rehabilitation and return to full function. REFERENCES 1.Ahstrom JP: Osteochondral fracture in the knee joint associated with hypermobility and dislocation of the patella. J Bone Joint Surg 47A: 1492-
1502, 1965 2. Frandsen PA, Kristensen H: Osteochondral fracture associated with dislocation of the patella: Another mechanism of injury. J Trauma 19: 195-
197, 1979 3. Hammerle CP, Jacob RP: Chondral and osteochondral fractures after luxation of the patella and their treatment. Arch Orthop Trauma Surg 97:
207-211,1980 4.
Hughston
JC: Subluxation of the
patella. J Bone Joint Surg 50A: 1003-
1026,1968 5. Milgram JW: Case report 333. Skeletal Radiol 14: 231-234, 1985 6. Rorabeck CH, Bobechko WP: Acute dislocation of the patella with osteochondral fracture: A review of eighteen cases. J Bone Joint Surg 58B:
237-240,1976 7. Turek SL:
Orthopaedics Principles Lippincott, 1984, pp 1333-1335
&
Their
Applications. Philadelphia,
8. Watson-Jones R: Fractures and Joint Injuries. Sixth edition. Churchill Livingstone, 1982, pp 1062-1065
JB
Edinburgh,
Department of Orthopaedic Surgery,
Dislocation of the patella is a common disorder of the knee joint. It is seen most frequently in the adolescent female population.’ Osteochondral fractures complicate approximately 5% of all acute patellar dislocations.’ This fracture will usually occur at the medial side of the patella or, more seldomly, on the lateral margin or the lateral femoral condyle.4,5.8 This case report documents a unique presentation of a first-time patellar dislocation in an adult man during a golfing outing.
Osteopathic Hospital, Flint, Michigan
he was unable to actively extend his knee. However, if passively extended, he could maintain the position. ThighB atrophy was noted again, but quadriceps function was felt to be intact, with 4+ strength measurement. In the supine position the patient demonstrated apprehension with laterally directed pressure of the patella, but no obvious patellofemoral laxity was appreciated. There was mild synovitis of the knee, but no effusion identified. Neither joint line tenderness nor lateral femoral condyle discomfort was identified. With passive flexion and extension of the knee there was patellofemoral crepitus and pain. Ligaments were found to be unaffected; the Lachman and McMurray maneuvers were negative. The left lower extremity examination was unremarkable. The alignment was similar to that of the right, also with a Q angle of 9°. The left patella was found to be well seated in the trochlear groove with no apparent laxity or tendency
CASE REPORT A 36-year-old man presented for orthopaedic consultation 6 weeks after the onset of pain in his right knee. He originally sustained injury while playing golf. During the followthrough phase of his swing after a drive, he felt a &dquo;snap&dquo; within his right knee. He was unable to continue playing, although he could ambulate independently. He sought medical attention at a local emergency department where radiographic examination proved negative. It was recommended that he use crutches and he was placed in a knee immobilizer. Seven days later he discontinued use of the crutches, and at 14 days after injury he stopped using the knee immobilizer. However, he continued to have anterior right knee pain and was unable to actively extend his right knee. His functional impairment was a restricted ability to negotiate stairs. Because of these complaints and continued swelling he sought further medical attention. Physical examination revealed a cooperative patient who was 5 feet, 10 inches tall and weighed 160 pounds. He ambulated with a slight limp and favored his right leg. There was moderate thigh atrophy on the right side when the patient was in the standing position. The alignment of the involved extremity was otherwise within normal limits, with a Q angle of 9°. A particularly unusual finding was that when the patient was examined in the sitting position, with the knee flexed, * Address correspondence and reprint requests to: 9141 Grant Street, Suite 10, Thornton, CO 80229.
Flint
toward subluxation
or
dislocation.
Radiographs from the original emergency department visit were reviewed and found to be unremarkable. Repeat radiographs demonstrated bony fragments in the suprapatellar pouch region, which were seen in the lateral view (Fig. 1). Based on the patient’s history and physical findings, it was recommended that he undergo arthroscopic surgery. During surgery, the menisci, cruciate ligaments, and tibial articular surface were found to be within normal limits. Inspection of the lateral femoral condyle demonstrated an irregularity consistent with healing of a bony defect and cartilaginous injury along the middle arc region of the lateral aspect of the lateral femoral condyle. Visualization of the patellofemoral compartment revealed that the entire patellar articular surface had been avulsed. This damage was obviously full-thickness in nature. New fibrocartilaginous tissue was noted to have completely covered the defect. Further inspection of the suprapatellar pouch revealed a large osseous cartilaginous body scarred down to the anterior aspect of the femur just above the trochlear groove. This fragment was mobilized and removed. It measured 2.5 x 3.0 x 0.5 cm. The size of the fragment and its contour were consistent with the large patellar defect.
Christopher Isaacs, DO, 613
614
DISCUSSION
Figure 1. Lateral radiograph demonstrating bony fragment (arrow) in the suprapatellar region. At 2 weeks after surgery, the patient reported improvement in tenderness and function. Examination revealed soft tissue swelling and effusion. Range of motion of the knee was 0° to 90°. Straight leg raising, hip abduction, and range of motion exercises were instituted, along with ice massage. At 4 weeks he continued to show improvement. However, a 1+ effusion (on a scale of 1 to 4) had persisted. The patient demonstrated full extension against gravity with minimal discomfort and crepitus. Progressive resistance straight leg raising exercises were instituted along with the use of an exercise bike. At 10 weeks the patient demonstrated full range of motion. No synovitis or effusion was appreciated; quadriceps tone and bulk showed improvement. He was given a prescription for a patella stabilizing brace and allowed to return to full
activity.
Dislocation of the patella is usually the result of indirect trauma. The most common mechanism of injury is forced inward rotation of the femur against a fixed externally rotated tibia in combination with contraction of the quadriceps mechanism.l.2. 7.8 Osteochondral fracture of the patella or the femoral condyle, or both, occurs as the patella slides tangentially over the surface of the lateral femoral condyle with the knee in the flexed position.l.4-6,8 In the case presented here, the patient was able to accurately describe the mechanism of injury. It would at first seem most unusual for this injury to occur during the action of swinging a golf club. However, it can be biomechanically visualized that the follow-through phase of the stroke would involve internal rotation of the femur on a tibia fixed by a cleated golf shoe, with the knee in a partially flexed position. It must be reemphasized that this injury was unusual in that it was a first-time dislocation in an adult man in a nontraumatic situation.l°2 In addition, the presentation of a patient with loss of active extension with no disruption of the quadriceps mechanism has not been reported previously. We believe this loss of ability to extend the knee was secondary to impingement of the osteochondral fragment embedded in the synovium on the anterior femur. At the time of arthroscopic surgery, the femoral condyle injury was seen to have already begun healing. The large defect of the articular surface of the patella was covered with fibrocartilage. Removal of the large osteochondral fragment and other debris eliminated a significant portion of the patient’s discomfort and allowed for his rehabilitation.’ Had we been able to examine the injury soon after it occurred, fixation of an osteochondral fragment of this size might have been possible.3.8 As it was, this patient had successful rehabilitation and return to full function. REFERENCES 1.Ahstrom JP: Osteochondral fracture in the knee joint associated with hypermobility and dislocation of the patella. J Bone Joint Surg 47A: 1492-
1502, 1965 2. Frandsen PA, Kristensen H: Osteochondral fracture associated with dislocation of the patella: Another mechanism of injury. J Trauma 19: 195-
197, 1979 3. Hammerle CP, Jacob RP: Chondral and osteochondral fractures after luxation of the patella and their treatment. Arch Orthop Trauma Surg 97:
207-211,1980 4.
Hughston
JC: Subluxation of the
patella. J Bone Joint Surg 50A: 1003-
1026,1968 5. Milgram JW: Case report 333. Skeletal Radiol 14: 231-234, 1985 6. Rorabeck CH, Bobechko WP: Acute dislocation of the patella with osteochondral fracture: A review of eighteen cases. J Bone Joint Surg 58B:
237-240,1976 7. Turek SL:
Orthopaedics Principles Lippincott, 1984, pp 1333-1335
&
Their
Applications. Philadelphia,
8. Watson-Jones R: Fractures and Joint Injuries. Sixth edition. Churchill Livingstone, 1982, pp 1062-1065
JB
Edinburgh,
