Proximal Physis Research Articles

Physiolysis for correction of clinodactyly in children.

Congenital clinodactyly is a lateral deviation of a finger frequently caused by an abnormal middle phalanx (trapezoidal or triangular delta phalanx). The physis extends longitudinally on the short side of the middle phalanx. Resection of the abnormal longitudinal physis and fat graft interposition (physiolysis) has been reported to correct the lateral finger deviation in growing children. We reviewed 35 fingers that had a physiolysis procedure. The age at surgery varied from 2.9 to 10.9 years (mean, 6.6 y), the preoperative angulation was 20 degrees to 29 degrees in 9 fingers, 30 degrees to 39 degrees in 16 fingers, and 40 degrees or more in 10 fingers. Thirty-one fingers presented a trapezoidal phalanx and 4 fingers a triangular phalanx. Ten fingers had a second surgery using the same procedure. Follow-up time ranged from 1.2 to 5.3 years (mean, 3.2 y). After 1 procedure the degree of correction varied from 0 degrees to 30 degrees (mean, 11.1 degrees). The residual angulation was <15 degrees in 8 fingers, 15 degrees to 19 degrees in 4 fingers, 20 degrees to 29 degrees in 15 fingers, 30 degrees to 39 degrees in 6 fingers, and > or =40 degrees in 2 fingers. Correction obtained in the trapezoidal phalanges was better (mean 12.5 degrees) than in the triangular phalanges (mean, 2.8 degrees). The fingers presenting a more severe preoperative deformity (angulation > or =40 degrees) had a better correction (mean, 20 degrees) compared with fingers with a lesser deformity (mean, 7.5 degrees). The correction was also better in children who had surgery before 6 years of age (mean, 17.9 degrees) compared with older children (mean, 6.5 degrees). A second physiolysis procedure was not beneficial in 8 of 10 fingers reoperated and 2 premature fusions of the proximal transverse physis were found among these 10 fingers. There were no other complications. The physiolysis procedure is simple and effective, particularly in children presenting with a trapezoidal phalanx who have surgery before 6 years of age.

Osteochondritis of the base of the first metacarpal following a physeal injury

An eight year old girl sustained a Salter–Harris II fracture of the proximal physis of the dominant thumb metacarpal by tumbling over a gate (Fig. 1). Eleven days later she was able to mobilise the thumb and was discharged from the clinic.

True skier's thumb in childhood

Acute rupture of the ulnar collateral ligament (UCL) of the thumb from forced abduction of the proximal phalanx is known as skier’s thumb or, the common misnomer, gamekeeper’s thumb. In children, the UCL of the thumb rarely ruptures in isolation. The imparted energy usually dissipates across the proximal phalangeal physis. Occasionally, a ‘pseudo’ injury occurs with a type I or type II Salter–Harris (SH) fracture but an intact UCL (Fig. 1A), particularly in younger children [1]. In these cases, abduction stress of the metacarpophalangeal joint (MCP) then causes angulation at the physis, thus mimicking UCL rupture. We report a rare case of ‘true’ skier’s thumb associated with a SH II fracture of the base of the proximal phalanx, and explain the mechanism of injury.

The Effect of Osteogenic Protein-1 in an In Vivo Physeal Injury Model

The physis has limited ability to undergo repair, and injury may result in growth arrest. Osteogenic protein-1 promotes bone formation in diaphyseal defects, chondrocyte proliferation, and matrix synthesis. The authors' goal was to determine if the presence of osteogenic protein-1 in a defect involving the physis would promote cartilage repair, and in doing so, to determine the effect of osteogenic protein-1 on physeal growth. An ovine model of growth plate damage was used, in which the proximal medial physis of the tibia was partially ablated. The defect was filled with a Type I collagen paste containing osteogenic protein-1 (350 microg) or collagen alone. Growth rate was measured at 4, 14, and 56 days, and the defects were analyzed histologically at 4, 14, and 56 days. Bone bridge formation occurred within the defect site. However, osteogenic protein-1 promoted outgrowth of the adjacent physeal cartilage. The physeal cartilage underwent expansion until the mineral forming within the defect site blocked its progress. The effect was localized because only that portion of the physis at the defect margin appeared to be affected.

Fractures of the Proximal Radial Head and Neck in Children with Emphasis on Those That Involve the Articular Cartilage

This is a review of 116 children who had a fracture of the proximal radial head or neck over a 15-year period. Of 33 teenagers with closed physes, 17 (52%) had intraarticular involvement. Of 83 younger children with an open proximal radial physis, six (7%) had an intraarticular fracture (Salter-Harris type III or IV). Of the 17 patients with closed physes and intraarticular fracture, 13 had adequate follow-up. There were eight excellent, three good, one fair, and one poor results. Of the six children with open physes and intraarticular fracture, there were one good and five poor results. This study confirms that intraarticular fracture of the radial head is much more common if the proximal radial physis is closed. In addition, this review indicates that the prognosis is extremely poor for children who have a radial head intraarticular fracture that also involves an open physis (Salter-Harris types III and IV), particularly when the fracture is treated initially nonoperatively. Displaced proximal radial fractures that involve both physeal and articular cartilage may be occult, and as with all physeal and intraarticular fractures, anatomic reduction (open if necessary) is mandatory.

Ischemic gangrene of the newborn

Vascular insufficiency and ischemic gangrene of the extremity is a rare, but serious complication seen in newborns. We present a newborn who developed ischemic gangrene of the left lower extremity due to prematurity, umbilical artery catheterization and septicemia, requiring a below knee amputation. Inadequate initial management, parental neglect and delayed diagnosis were other contributing factors for the undesirable outcome. Recognition of predisposing factors and identification of the high risk neonates are the major prerequisites for either appropriate measures or a successful outcome. In case of failure despite all supportive measures and proper management, amputation should be delayed until a clear demarcation has occurred. During surgery, the adjacent proximal physis should be preserved.

Premature closure of the proximal physis of the humerus in a dog as a result of harvesting a cancellous bone graft

Premature closure of the proximal physis of the humerus in a dog as a result of harvesting a cancellous bone graft

Free vascularized growth-plate transfer after bone tumor resection in children.

Limb-salvage surgery is the standard care for most malignant tumors affecting the extremities, and a vascularized fibula transfer is probably the most popular microsurgical option to reconstruct long-bone defects. Skeletal reconstruction after bone-tumor resection involving the metepiphysis of a growing child can be successfully achieved with a vascularized fibula graft incorporating the proximal physis and active growth plate. Such a procedure has been utilized in 12 children under the age of 10 years who had malignant bone tumors located in the upper limb (3 in the distal radius, 9 in the proximal humerus). The follow-up ranged between 4 years and 3 months. Ten grafts were supplied by the anterior tibial artery, and two by the peroneal artery. The average growth rate of the grafts based on the former artery has been more than 1 cm per year, ranging between 0.75 and 1.33 cm. The authors describe a modified operative technique and discuss the clinical results of the procedure which offers a satisfactory skeletal reconstruction and prevents future limb-size discrepancy.

Physeal form of the longbones of the foal

The possible relationship between physeal diseases and physeal form prompted investigation of change in steepness of the physis in young foals. The distal and proximal aspects of the longbones were sawn sagittally in the right and frontally in the left bones. The slabs were washed to remove saw debris, arranged in order and inspected. The proximal physes had a flat or gently arched form, without obvious inclination. In the distal physes there were distinct inclinations. Inspection of an identical slab from the medial aspect of the distal radius of two series of foals of different breeds showed that the degree of inclination of the physis with respect to the long axis of the bone increased with age. In a further series of foals, the angle of inclination was measured from radiographs of identical sagittal and frontal slabs of the distal radius. A line drawn through the secondary spongiosa was produced to intersect a line drawn along the physis where it was mostly steeply inclined, and the angle measured. The angle decreased (physeal inclination increased) with increasing age, up to 35–90 days. The steepness in the lateral aspect of the physis was similar to that in the medial aspect, although evident in a different plane.

Growth of the Proximal Fibular Physis and Remodeling of the Epiphysis after Microvascular Transfer. A Case Report*

The advantages of use of vascularized grafts as compared with use of non-vascularized grafts have been demonstrated experimentally and clinically in skeletally mature individuals. These advantages include skeletal healing without creeping substitution22 of the graft from the surrounding host bone8,29; more rapid incorporation and union9; lower rates of fracture, infection, resorption, and non-union3,12,31; the option of using the grafts for the treatment of established infections8,15 and segmental defects larger than five centimeters3,8; greater initial strength8,18,25; remodeling in a manner similar to that of viable bone8,16,18,25; the ability to respond to biomechanical loading physiologically9,13,18,25; increased hypertrophy7; and a decreased duration of immobilization after implantation11. Another, theoretical advantage of use of a microvascularized fibular graft is the potential for growth of the graft through the open physis. Continued growth of the physis after vascularized bone transfer was demonstrated by Weiland in a dog model as reported by Burwell et al.4. Microvascular transfer of the combined physis and epiphysis after digital amputation has resulted in longitudinal growth in children20. We describe the case of a patient who had excision of an osteosarcoma of the proximal part of the humerus. The skeletal defect was treated with insertion of a microvascularized free fibular graft, including the proximal physis and epiphysis, into the glenohumeral joint. The proximal physis remained open and demonstrated continued growth and remodeling four years after the transfer. An eight-year-old girl was seen because she had had pain in the right shoulder for three months. There was no history of trauma. The findings …

Reduction and operative fixation ofproximal tibial physeal fractures

Types I and II growth mechanism fractures of the proximal tibia generally may be reduced closed and maintained by nonoperative methods. However, operative stabilization of even these patterns may be necessary in more complex injuries such as a floating knee or multiple trauma.Types III and IV injuries of the proximal physis and injuries at the periphery of the epiphysis, particularly the tibial spines and tibial tuberosity, usually require open reduction and internal fixation. Techniques of closed and operative management of these various injury patterns are described.

Longitudinal growth from the proximal femoral growth centers in the rabbit.

We selectively ablated the proximal growth centers of the femur in 3-week-old white New Zealand rabbits to study the contribution of each physis to bone length. The results were compared with the normal growth pattern determined in our previously published study. Growth in 10 femora with ablated greater trochanteric apophyses was normal as was the rate of growth for the 11 femora in which the proximal physis and femoral head were excised. Following femoral head excision, growth of 10 greater trochanteric apophyses, transferred in situ with muscular pedicle, was delayed initially, then increased at a rate very different from the control trochanteric growth. On the basis of this animal study, we support substitution of the greater trochanteric apophysis for an injured femoral neck physis to provide growth in the length of the femur.

Remodelling of angular deformity after femoral shaft fractures in children.

We reviewed 28 children with unilateral middle-third fractures of the femoral shaft who had an angular deformity after union of 10 degrees to 26 degrees. At an average follow-up of 45 months (20 to 66), we measured remodelling of the proximal physis, the distal physis and the femoral shaft. The average correction was 85% of the initial deformity. We found that 74% of correction occurred at the physes and only 26% at the fracture site. Neither the direction nor the magnitude of the angulation much influenced the degree of remodelling. Younger children remodelled only a little better than older children. We conclude that in children under 13 years of age, malunion of as much as 25 degrees in any plane will remodel enough to give normal alignment of the joint surfaces.

Use of orthopedic markers for quantitative determination of proximal radial and ulnar growth in foals

Summary Cortical bone screws were implanted into the proximal portion of the right and left radius and ulna of 6 newborn Quarter Horse foals as radiographic markers for measurement of growth. Distance between markers on a lateral radiographic view was measured. Radiographs were taken at 2-week intervals until the horses were 8 weeks old, at 4-week intervals until they were 48 weeks old, and at 12-week intervals until they were 72 weeks old. The proximal radius and ulna grew at similar rates during the 72-week period of evaluation, and growth continued throughout 72 weeks. The proximal radius grew 3.5 cm, and the ulna grew 3.4 cm. Although the rates of growth were similar, growth from the ulnar physis contributed only to the length of the olecranon; growth was not transmitted to the ulnar diaphysis distal to the cubital joint. The proximal radius slid distally in relation to the ulna as growth occurred at the proximal radial physis. These findings suggest that transfixing the ulna to the radius while growth is occurring at the proximal radial physis impedes the natural shifting process, and subluxation of the elbow can result. Severity of subluxation would be inversely related to the age of the horse at the time of transfixation.

A XERORADIOGRAPHIC STUDY OF THE DEVELOPING QUARTERHORSE FOREDIGIT AND METACARPOPHALANGEAL REGION FROM SIX TO TWELVE MONTHS OF AGE

The purpose of the project was to provide a reference for radiographic anatomy of the developing equine foredigit and metacarpophalangeal region. Using xeroradiographic techniques, both foredigits and metacarpophalangeal regions of six Quarter Horse foals were radiographed at 1 day of age and then at 2‐week intervals until the foals were 6 weeks old. The foals were then radiographed at 4‐week intervals until they were 12 months old. The period from birth to 6 months has been described in a previous report. This paper deals with the period from 6 to 12 months of age. Lateromedial and dorsopalmar xeroradiographs of each foredigit and metacarpophalangeal region and a dorsal 65° proximal‐palmarodistal oblique view of the distal part of the digit were made at each examination. Foals were weighed and were measured at the withers immediately prior to each examination. Representative xeroradiographs were selected and appropriately labeled to demonstrate normal radiographic anatomy of these regions. Earliest radiographic visualization of distal epiphyseal ossification in metacarpal 2 and metacarpal 4 was extremely variable and ranged from 4 to 38 weeks. It was not possible to determine accurately the ages at which distal physes of the small metacarpal bones closed. In one foal, three of four of these physes were closed at 26 weeks, while in another foal, none had closed when last radiographed at 54 weeks. Radiographic closure of the proximal physis of the middle phalanx ranged from 18 to 30 weeks (mean = 26 weeks). Radiographic closure of the proximal physis of the proximal phalanx ranged from 22 to 38 weeks (mean = 30 weeks). Radiographic closure of the distal physis of metacarpal 3 ranged from 18 to 38 weeks (mean = 29 weeks).

Radial growth and function of the forearm after excision of the radial head. A study of growing macaque monkeys.

In five immature macaque monkeys, the right radial head was excised and the left forearm served as a control. Growth of each radius, ulna, and proximal and distal physis was followed for eight years. Total radial growth was slightly less on the side that was operated on than it was on the control side. After excision of the radial head, 95 per cent of radial growth came from the distal physis, compared with 71 per cent on the control side. A regenerated radial head, which had an irregular surface of fibrocartilaginous tissue, accounted for the remainder of growth on the side that had been operated on. Incongruous contact of articular surfaces resulted in degenerative changes in the capitellum. The arms that had been operated on were left with a flexion contracture that was an average of 12 degrees greater than that of the normal elbows, and they had a carrying angle that was an average of 6 degrees greater than that on the normal side. The arc of pronation and supination was decreased for the forearms that had been operated on, but motion of the wrist was unaffected. In our study, excision of the radial head in growing monkeys resulted in minimum radial shortening, slight deformity of the elbow, and moderate impairment of rotation of the forearm.

A XERORADIOGRAPHIC STUDY OF THE DEVELOPING EQUINE FOREDIGIT AND METACARPOPHALANGEAL REGION FROM BIRTH TO SIX MONTHS OF AGE

The purpose of the project was to provide a reference for radiographic anatomy of the developing equine foredigit and metacarpophalangeal region. Using xeroradiographic techniques, both foredigits and meta‐carpophalangeal regions of six Quarter Horse foals were radiographed at one day of age and at two‐week intervals until the foals were six weeks old. The foals were then radiographed at four‐week intervals until they were 12 months old. This report deals specifically with the first six months of postnatal development. Lateromedial and dorsopalmar xeroradiographs of each foredigit and metacarpophalangeal region and a dorsal 65° proximal‐palmarodistal oblique view of the distal part of the digit were made for each examination. The foals were weighed and measured at the withers immediately prior to each examination. Representative xeroradiographs were selected and appropriately labeled to demonstrate normal radio‐graphic anatomy of these regions. First radiographic appearance of distal epiphyseal ossification in metacarpal 2 and metacarpal 4 was extremely variable and ranged from four to 38 weeks. Radiographic closure of the proximal physis of the middle phalanx ranged from 18 to 30 weeks (mean = 26 weeks). Radiographic closure of the proximal physis of the proximal phalanx ranged from 22 to 38 weeks (mean = 30 weeks). Radiographic closure of the distal physis of metacarpal 3 ranged from 18 to 38 weeks (mean = 29 weeks). When xeroradiographic physeal closure times were compared with scintigraphic closure times from a companion study, results correlated very well. A crena marginis solearis was observed in ten of 12 forelimbs (83.3%); its first radiographic appearance ranged from four to 22 weeks (mean = 11–12 weeks). A consistent groove in the hoof wall, which formed near the time of birth and moved distally at about 3 mm per week, was noted. The groove's distance from the proximal hoof border may be useful in age estimation of foals less than 18–20 weeks old.

Traumatic Separation of Epiphyses

Four types of physeal fracture-separations, defined by the Salter-Harris classification, were created experimentally in the proximal physis of the right tibia of immature rats. The four types are: Type I, pure epiphyseal separation; Type II, separation of the epiphysis with a metaphyseal fracture; Type III, partial epiphyseal separation with a vertical fracture of the epiphysis; and Type IV, vertical epiphyseal and metaphyseal fractures. A sham operation performed on the left tibia served as the control. The animals were killed at various intervals up to 25 days after the operation. The findings were assessed by roentgenographic, histologic, and vessel injection methods. For Types I and II morphometric analyses were also performed. The influence of various types of lesions on the growth rate and the healing process was documented. For Types I and II lesions there was a transitory growth arrest and an increased thickening of the zone of hypertrophic cells. The alterations regressed after Day 15, and by day 25, a nearly normal plate was seen. For Type III lesions an angular deformity of the tibia occurred that increased with time. For Type IV lesions, a step-off developed on the articular surface that became more severe with time. Early vascular anastomoses between the epiphysis and the metaphysis led to the formation of bone bridges in Type III and Type IV lesions.

Physeal Fractures in the Horse:I. Classification and Incidence

Seventy appendicular skeletal physeal fractures in 67 horses were reviewed and classified using the Salter‐Harris classification. All the horses were less than 2 years old (mean age at injury 6.2 months). The mean age at injury for pressure physeal fractures (5.2 months) was significantly less (p &lt; .05) than for traction physeal fractures (8.3 months). The majority (67.2%) of the horses were female. Forty‐eight (69%) pressure physes and 22 (31%) traction physes were affected. The most common pressure and traction physeal fracture sites were the proximal femoral physis and the proximal ulnar physis, respectively. Sixty‐seven physeal fractures were classified: 14 as Type I (20.9%), 42 as Type II (62.7%), six as Type III (8.9%), and five as Type IV (7.5%). Forty‐six pressure physeal fractures were classified: six as Type I (13.0%), 30 as Type II (65.2%), five as Type Hi (10.9%), and 5 as Type IV (10.9%).

Changes in tibiofibular relationships due to growth disturbances after ankle fractures in children.

We analyzed the longitudinal growth of the distal tibial and fibular physes and the longitudinal displacement of the distal metaphysis and epiphysis of the fibula relative to the distal metaphysis and epiphysis of the tibia during growth using a roentgenstereophotogrammetric technique in eight children: six with a traumatic growth disturbance in one or both of the distal tibial and distal fibular physes and two with a normal ankle. In the normal ankles the distal fibular metaphysis moved distally in relation to the distal tibial metaphysis and the growth in the distal fibular physis was slower than that in the distal tibial physis. Growth arrest in the distal fibular physis and continued growth in the distal tibial physis resulted in distal displacement of the fibular metaphysis relative to the tibial metaphysis, probably due to traction on the distal ligaments of the fibula or more rapid growth in the proximal fibular physis than in the proximal tibial physis, or both. Valgus deformity of the ankle developed when the growth of the distal tibial physis exceeded the distal sliding of the fibula, as shown by the stereophotogrammetric analyses and orthoroentgenograms. Growth arrest in the distal tibial physis and continued growth in the distal fibular physis resulted in proximal sliding of the fibula, as shown by the roentgenstereophotogrammetric analyses and serial orthoroentgenograms. This mechanism compensated to some extent for the overgrowth of the fibula. Simultaneous growth arrest in both the distal tibial and the distal fibular physis was associated with movement of the distal end of the fibula in a distal direction relative to the tibia, probably due to the more rapid growth in the proximal fibular physis than in the proximal tibial growth plate. Therefore, growth arrest of the distal tibial or fibular physis may result in either proximal or distal sliding of the fibular metaphysis in relation to the tibial metaphysis. Probably growth arrest in the distal fibular physis has a less favorable prognosis than arrest in the distal tibial physis, because after tibial arrest proximal sliding of the fibula may compensate for overgrowth of the fibula better than distal sliding of the fibula can compensate for fibular arrest and overgrowth of the tibia.