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Intraarticular fractures of the distal radius: A cadaveric study to determine if ligamentotaxis restores radiopalmar tilt
Intraarticular fractures of the distal radius: A cadaveric study to determine if ligamentotaxis restores radiopalmar tilt Nineteen fresh cadaver wrists were divested of all dorsal and palmar tissues to the wrist capsule and extrinic and intrinsic ligaments. A Frykman VII type fracture was established across the radiocarpal and radioulnar joints. The dorsal and palmar wrist ligaments were left intact. The forearms were stabilized in an arm board and an external fixation device and traction applied through a Kirschner wire at the base of the third metacarpal. Three positions of wrist flexion; neutral, 15, and 30 degrees, with 10 and 20 pounds oftraction were used to attempt to reestablish radiopalmar tilt. Only when the entire palmar ligamentous structures were transected at the radius was radiopalmar tilt reestablished. Ligamentotaxis alone is not a reliable method to reestablish radiopalmar tilt in intraarticular distal radius fractures. (J HAND SURG 1990;15A: 18-21.)
R. A. Bartosh, LCDR, USN, MC, and M. J. Saldana, CAPT, USN, Me, Portsmouth, Va.
Intraarticular fractures of the distal radius are frequently encountered in orthopaedic practice. The classic method of treatment is closed reduction and plaster of paris cast support. I External fixation or open reduction and internal fixation techniques are recommended for comminuted or unstable distal radial fractures that fail closed reduction or have intraarticular incongruity, 2·~ The preferred method of reduction is traction followed by variable amounts of palmar flexion of the wrist. The technique relies on ligamentotaxis on the fracture fragment to maintain reduction. 3 Radial length and radioulnar tilt are usually easily reestablished in distal intraarticular radial fractures because of the radiopalmar ligamentous attachments to the radial styloid. 6-lI Normal radiopalmar tilt of the distal radius in these fractures is seldom restored and frequently lost after reduction. From the Division of Hand Surgery, Orthopedic Department, Portsmouth Naval Hospital. Portsmouth, Va. Received fur publication Nov. 16, 1988; IIccepted in revised fonn March 11, 1989. No benefits in any fonn have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Reprint requests: M. J. Saldana, CAPT, USN, MC, Division of Hand Surgery, Orthopedic Department, Portsmouth Naval Hospital, Portsmouth, VA 23708. 3/1112622
18
THE JOURNAL OF HAND SURGERY
Fig. I. Arm secured to board through olecranon pin and traction applied by pin through third metacarpal base.
Vol. 15A, Nu. I
January 1990
lnlraarlicular fractures of distal radius
19
10 LB. TRACTION ~LMAR LIGAMENT CUl Fig. 2. Thirty degrees flexion plus 20 pounds of traction failed to reestablish radiopalmar till.
FIg. 3, Normal radiopalmac tilt: notice increased gap between capitate and lunate (dark arrow) and lunate and radius without the restraint of the palmar ligaments.
This anatomic study was done to establish whether the radiopalmar tilt of the distal radius after intraarticular fractures could be reestablished employing ligamentotaxis.
wrist were taken of each forearm to define the configuration of the articular surface of the distal radius. A Frykmann type Vll fracture 9 was established with a I-inch straight osteotome placed on the radial styoid and driven across the distal radius through the radiocarpal and radioulnar joints. This fracture, impacted by pushing the hand into the radius, established a dorsal intraarticular bony fragment with intact dorsal wrist ligaments. Three positions (neutral flexion, 15 degrees fiexion, and 30 degrees flexion), with two separate amounts of distraction, (10 pounds and 20 pounds) were used in an attempt to reduce the fracture. A lateral radiograph was taken to determine if the radiopalmar tilt had been reestablished for each position of flexion and distraction (Fig. 2). The entire palmar ligamentous complex was then transected at the radius and further evaluation was made in the neutral flexion position with ten pounds of distraction (Fig. 3). The length between the distal radius and the base of
Materials and methods Twenty wrists in 10 fresh cadavers were prepared for study by removing the skin and all soft tissues to the level of the dorsal and palmar wrist ligaments. An external fixation device was applied using two 3 mm pins in the second metacarpal and two 4 mm pins in the radius. For ease of radiographic evaluation, the external fixation device was used to lock the wrist into position after each reduction maneuver. A large threaded Steiman pin placed through the proximal ulna was used to stabilize the forearm on a large wooden frame. Traction was achieved by pulling on a 2.0 mm smooth Kirschner wire placed through the base of the third metacarpal and attached to a Kirschner bow (Fig. 1). Initial lateral and anteroposterior x-ray films of the
20
The lournal of HAND SURGERY
Bartosh and Sa/dana
Fig. 4. Angles drawn on dorsum of wrist with arrow pointing to triquetrum.
Table I. Proximal dorsal ligamentous angles between radiolunotriquetral and dorsal intercarpal ligament _ _ _ _ _ ,----JO-lb--Neutral 15 Flexion 30 Fieldon
(31) 31-39 degrees (40) 38-43 degrees (40) 38-41 degrees
Table n. Distal dorsal ligamentous angles between dorsal intercarpal ligament and line drawn on intrinsic distal row ligaments
20 Jb (41) 40-45 degrees (42) 39-45 degrees (43) 40-47 degrees
10 lb Neutral 15 Flexion 30 Flexion
(34) 25-39 degrees (39) 38·40 degrees (41) 39·42 degrees
201b
(36) 35-37 degrees (41) 39-44 degrees (43) 40-48 degrees
(), Avcl1Ige.
( ). Avernge.
the third metacarpal was measured in the anteroposterior radiograph. The increase of this length in millimeters in each position measured was noted as carpal distraction. The dorsal wrist ligaments were outlined by drawing three lines: on the radio-luno-triquetral extrinsic ligament, on the dorsal intercarpal ligament connecting with the first line at the triquetrum, across the distal carpal row. These three lines formed a Z on the dorsum of the wrist (Fig. 4). The two acute angles formed by the Z were measured in each of the positions of flexion and distraction.
were transected. Flexion and distraction alone failed to reestablish radiopalmar tilt (Fig. 3). Using chi square analysis the above findings were highly significant. Chi square equaled 34.1. Allowing 1 degree of freedom, this was significant at the 0.001 level. The angles created by the lines drawn on the dorsal wrist ligaments increased in size through each of the positions of flexion and distraction (Tables I and II).
Results The appropriate fracture pattern was established in 19 out of 20 wrists prepared. The average carpal distraction measured 3 mm on x-ray films before the palmar wrist ligaments were cut. Normal radiopalmar tilt was reestablished in neutral flexion with 10 pounds of traction only when the entire palmar wrist ligaments
Discussion Fracture fragment reduction is dependent on ligamentotaxis when external fixation or pins and plaster techniques are used to reduce and maintain an intraarticular distal radial fracture. 3 The fracture produced in the experiment falls into a Frykmann type VII 9 in that it involves only the radiocarpal and radioulnar joints. We chose this particular fracture pattern, because it was easily reproduced and left the dorsal wrist ligaments intact.
Vol 15A, No January 1990
The lIgaments of the wnst have been well descnbed 10 12 The palmar Wrist hgaments arc arranged 10 two V-shaped configurations The apex of the V formed by the radlOlunate ligament and the ulnolunate ligament IS located at the lunate The apex of the radlOscaphocapitate hgament and the arcuate hgament IS located at the capitate These ligaments arc stout, strong, and short 13 The average carpal distractIOn of 3 mm seen in the 19 Wrists was directly related to these short palmar ligaments commg to full stretch and arrestIng any further distractIOn On the other hand, the Z shape components of the dorsal wnst lIgaments are thmner and fewer than the palmar wnst ligaments 12 13 When tractIOn on the hand applied through the KlfSchner wire pulled on the dorsal wnsts ligaments, the limbs of the Z opened only to the length permitted by the arrestmg short palmar wnsts ligaments When cuttIng the palmar wnst ligaments elimInated their arrestlOg effect, ligamentotaxls effectively pulled the dorsal bony fragment to the appropnate radlOpalmar tilt (Fig 3) The ligaments of the Wrists, as other ligaments, are static structures When pulled out to length they arrest the motion of the JOInt that they bndge In distal radiUS fractures the palmar wnst ligaments Will pull out to length and pull on the distal radIUS fragment before the dorsal wnst ligaments have any tractIOn effect on the dorsal distal radiUS fragment FleXion of the Wrist, while applymg tractIOn, only Increases the accordIOn-lIke actIOn of the dorsal wnst ligaments preventmg effective hgamentotasls dorsally Regardless of the amount of tractIOn or fleXIOn, the average distractIOn of the nmeteen wnsts studied was 3 mm The palmar hgaments of these wnsts were not Involved 10 the fracture pattern and when pulled to maximum length arrested any further distractIOn Only when the arresting effect of the palmar Wrist ligaments was elimmated by transectiOn of these ligaments and tractIOn applied to the dorsal wnst hgamcnts alone, was radlOpalmar tIlt achieved
ConclUSion The short, stout, nature of the palmar wnst ligaments and the tendency for the dorsal ligaments to open like
lmraartlcular !raLtures of dIStal radllls
21
an accordIOn With fleXIOn of the Wrist, limits hgamentotaxls as the sale method for reestabhshlOg radlOpalmar ttlt of the radiUS m mtraartlcular distal radIUS fractures REFERENCES
2
3
4
5
6
7 8 9
10
II
12 13
Dobyns JH, Lmscheld RL In Rockwood CA, Green DP, eds Fractures In adults Philadelphia 18 LiPPinCott, 1984423-50 Cole JM, Obtetz BE Commmuted fractures of the distal end of the radIUS treated by skeletal transfiXIOn In plaster cast an end result study of thirty three eases J Bone Jomt Surg 1966,48A 931 Cooney WP III, Dobyns JR, Lmscheld RL External pm fixatIon for unstable Calles' fractures J Bone Jomt Surg 1980,62A 613 Cooney WP III, Dobyns JH, Lmscheld RL External pm fixation for unstable Colles' fracture J Bone Jomt Surg 1979,61A 840 Vidal J, Buscayret C, Paran M, et al Llgamentotaxls In Mears DC, ed External skeletal fixatIon Baltimore Williams & Wilkms, 1983 Gartland 11 Ir, Werley CW Evalualion of healed Colles' fracture 1 Bone lomt Surg 1951 33A 895 Thomas FB Reduction of Smith's fracture J Bone Jomt Surg 1957,39B 463-70 Melone CP Jr Articular fractures of the distal radIUS Orthop Chn North Am 1984,15217 Frykmann G Fracture of the distal radIUS mcludmg sequelee-shou1der-hand-finger syndrome, disturbance of the distal radioulnar JOInt and Impairment of nerve function a ehmcal and expenrnental study Acta Orthop Scand [Suppl] 1967,108 1-153 Telelsmk J Wnst anatomy, functIOn, and mJury Am Acad Orthop Surgeons 1nstruc Course Lee 1978,246187 Telelsmk J The hgaments of the WrIst J HAND SURG 1976,1 110-18 Mayfield JK The WrIst and Its disorders Philadelphia WB Saunders, 198845-54 Mayfield lK, Johnson RP, Kilcoyne RF The hgaments of the wnst and theIr functIOnal slgOificance Anat Rec 1976,186417
R. A. Bartosh, LCDR, USN, MC, and M. J. Saldana, CAPT, USN, Me, Portsmouth, Va.
Intraarticular fractures of the distal radius are frequently encountered in orthopaedic practice. The classic method of treatment is closed reduction and plaster of paris cast support. I External fixation or open reduction and internal fixation techniques are recommended for comminuted or unstable distal radial fractures that fail closed reduction or have intraarticular incongruity, 2·~ The preferred method of reduction is traction followed by variable amounts of palmar flexion of the wrist. The technique relies on ligamentotaxis on the fracture fragment to maintain reduction. 3 Radial length and radioulnar tilt are usually easily reestablished in distal intraarticular radial fractures because of the radiopalmar ligamentous attachments to the radial styloid. 6-lI Normal radiopalmar tilt of the distal radius in these fractures is seldom restored and frequently lost after reduction. From the Division of Hand Surgery, Orthopedic Department, Portsmouth Naval Hospital. Portsmouth, Va. Received fur publication Nov. 16, 1988; IIccepted in revised fonn March 11, 1989. No benefits in any fonn have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Reprint requests: M. J. Saldana, CAPT, USN, MC, Division of Hand Surgery, Orthopedic Department, Portsmouth Naval Hospital, Portsmouth, VA 23708. 3/1112622
18
THE JOURNAL OF HAND SURGERY
Fig. I. Arm secured to board through olecranon pin and traction applied by pin through third metacarpal base.
Vol. 15A, Nu. I
January 1990
lnlraarlicular fractures of distal radius
19
10 LB. TRACTION ~LMAR LIGAMENT CUl Fig. 2. Thirty degrees flexion plus 20 pounds of traction failed to reestablish radiopalmar till.
FIg. 3, Normal radiopalmac tilt: notice increased gap between capitate and lunate (dark arrow) and lunate and radius without the restraint of the palmar ligaments.
This anatomic study was done to establish whether the radiopalmar tilt of the distal radius after intraarticular fractures could be reestablished employing ligamentotaxis.
wrist were taken of each forearm to define the configuration of the articular surface of the distal radius. A Frykmann type Vll fracture 9 was established with a I-inch straight osteotome placed on the radial styoid and driven across the distal radius through the radiocarpal and radioulnar joints. This fracture, impacted by pushing the hand into the radius, established a dorsal intraarticular bony fragment with intact dorsal wrist ligaments. Three positions (neutral flexion, 15 degrees fiexion, and 30 degrees flexion), with two separate amounts of distraction, (10 pounds and 20 pounds) were used in an attempt to reduce the fracture. A lateral radiograph was taken to determine if the radiopalmar tilt had been reestablished for each position of flexion and distraction (Fig. 2). The entire palmar ligamentous complex was then transected at the radius and further evaluation was made in the neutral flexion position with ten pounds of distraction (Fig. 3). The length between the distal radius and the base of
Materials and methods Twenty wrists in 10 fresh cadavers were prepared for study by removing the skin and all soft tissues to the level of the dorsal and palmar wrist ligaments. An external fixation device was applied using two 3 mm pins in the second metacarpal and two 4 mm pins in the radius. For ease of radiographic evaluation, the external fixation device was used to lock the wrist into position after each reduction maneuver. A large threaded Steiman pin placed through the proximal ulna was used to stabilize the forearm on a large wooden frame. Traction was achieved by pulling on a 2.0 mm smooth Kirschner wire placed through the base of the third metacarpal and attached to a Kirschner bow (Fig. 1). Initial lateral and anteroposterior x-ray films of the
20
The lournal of HAND SURGERY
Bartosh and Sa/dana
Fig. 4. Angles drawn on dorsum of wrist with arrow pointing to triquetrum.
Table I. Proximal dorsal ligamentous angles between radiolunotriquetral and dorsal intercarpal ligament _ _ _ _ _ ,----JO-lb--Neutral 15 Flexion 30 Fieldon
(31) 31-39 degrees (40) 38-43 degrees (40) 38-41 degrees
Table n. Distal dorsal ligamentous angles between dorsal intercarpal ligament and line drawn on intrinsic distal row ligaments
20 Jb (41) 40-45 degrees (42) 39-45 degrees (43) 40-47 degrees
10 lb Neutral 15 Flexion 30 Flexion
(34) 25-39 degrees (39) 38·40 degrees (41) 39·42 degrees
201b
(36) 35-37 degrees (41) 39-44 degrees (43) 40-48 degrees
(), Avcl1Ige.
( ). Avernge.
the third metacarpal was measured in the anteroposterior radiograph. The increase of this length in millimeters in each position measured was noted as carpal distraction. The dorsal wrist ligaments were outlined by drawing three lines: on the radio-luno-triquetral extrinsic ligament, on the dorsal intercarpal ligament connecting with the first line at the triquetrum, across the distal carpal row. These three lines formed a Z on the dorsum of the wrist (Fig. 4). The two acute angles formed by the Z were measured in each of the positions of flexion and distraction.
were transected. Flexion and distraction alone failed to reestablish radiopalmar tilt (Fig. 3). Using chi square analysis the above findings were highly significant. Chi square equaled 34.1. Allowing 1 degree of freedom, this was significant at the 0.001 level. The angles created by the lines drawn on the dorsal wrist ligaments increased in size through each of the positions of flexion and distraction (Tables I and II).
Results The appropriate fracture pattern was established in 19 out of 20 wrists prepared. The average carpal distraction measured 3 mm on x-ray films before the palmar wrist ligaments were cut. Normal radiopalmar tilt was reestablished in neutral flexion with 10 pounds of traction only when the entire palmar wrist ligaments
Discussion Fracture fragment reduction is dependent on ligamentotaxis when external fixation or pins and plaster techniques are used to reduce and maintain an intraarticular distal radial fracture. 3 The fracture produced in the experiment falls into a Frykmann type VII 9 in that it involves only the radiocarpal and radioulnar joints. We chose this particular fracture pattern, because it was easily reproduced and left the dorsal wrist ligaments intact.
Vol 15A, No January 1990
The lIgaments of the wnst have been well descnbed 10 12 The palmar Wrist hgaments arc arranged 10 two V-shaped configurations The apex of the V formed by the radlOlunate ligament and the ulnolunate ligament IS located at the lunate The apex of the radlOscaphocapitate hgament and the arcuate hgament IS located at the capitate These ligaments arc stout, strong, and short 13 The average carpal distractIOn of 3 mm seen in the 19 Wrists was directly related to these short palmar ligaments commg to full stretch and arrestIng any further distractIOn On the other hand, the Z shape components of the dorsal wnst lIgaments are thmner and fewer than the palmar wnst ligaments 12 13 When tractIOn on the hand applied through the KlfSchner wire pulled on the dorsal wnsts ligaments, the limbs of the Z opened only to the length permitted by the arrestmg short palmar wnsts ligaments When cuttIng the palmar wnst ligaments elimInated their arrestlOg effect, ligamentotaxls effectively pulled the dorsal bony fragment to the appropnate radlOpalmar tilt (Fig 3) The ligaments of the Wrists, as other ligaments, are static structures When pulled out to length they arrest the motion of the JOInt that they bndge In distal radiUS fractures the palmar wnst ligaments Will pull out to length and pull on the distal radIUS fragment before the dorsal wnst ligaments have any tractIOn effect on the dorsal distal radiUS fragment FleXion of the Wrist, while applymg tractIOn, only Increases the accordIOn-lIke actIOn of the dorsal wnst ligaments preventmg effective hgamentotasls dorsally Regardless of the amount of tractIOn or fleXIOn, the average distractIOn of the nmeteen wnsts studied was 3 mm The palmar hgaments of these wnsts were not Involved 10 the fracture pattern and when pulled to maximum length arrested any further distractIOn Only when the arresting effect of the palmar Wrist ligaments was elimmated by transectiOn of these ligaments and tractIOn applied to the dorsal wnst hgamcnts alone, was radlOpalmar tIlt achieved
ConclUSion The short, stout, nature of the palmar wnst ligaments and the tendency for the dorsal ligaments to open like
lmraartlcular !raLtures of dIStal radllls
21
an accordIOn With fleXIOn of the Wrist, limits hgamentotaxls as the sale method for reestabhshlOg radlOpalmar ttlt of the radiUS m mtraartlcular distal radIUS fractures REFERENCES
2
3
4
5
6
7 8 9
10
II
12 13
Dobyns JH, Lmscheld RL In Rockwood CA, Green DP, eds Fractures In adults Philadelphia 18 LiPPinCott, 1984423-50 Cole JM, Obtetz BE Commmuted fractures of the distal end of the radIUS treated by skeletal transfiXIOn In plaster cast an end result study of thirty three eases J Bone Jomt Surg 1966,48A 931 Cooney WP III, Dobyns JR, Lmscheld RL External pm fixatIon for unstable Calles' fractures J Bone Jomt Surg 1980,62A 613 Cooney WP III, Dobyns JH, Lmscheld RL External pm fixation for unstable Colles' fracture J Bone Jomt Surg 1979,61A 840 Vidal J, Buscayret C, Paran M, et al Llgamentotaxls In Mears DC, ed External skeletal fixatIon Baltimore Williams & Wilkms, 1983 Gartland 11 Ir, Werley CW Evalualion of healed Colles' fracture 1 Bone lomt Surg 1951 33A 895 Thomas FB Reduction of Smith's fracture J Bone Jomt Surg 1957,39B 463-70 Melone CP Jr Articular fractures of the distal radIUS Orthop Chn North Am 1984,15217 Frykmann G Fracture of the distal radIUS mcludmg sequelee-shou1der-hand-finger syndrome, disturbance of the distal radioulnar JOInt and Impairment of nerve function a ehmcal and expenrnental study Acta Orthop Scand [Suppl] 1967,108 1-153 Telelsmk J Wnst anatomy, functIOn, and mJury Am Acad Orthop Surgeons 1nstruc Course Lee 1978,246187 Telelsmk J The hgaments of the WrIst J HAND SURG 1976,1 110-18 Mayfield JK The WrIst and Its disorders Philadelphia WB Saunders, 198845-54 Mayfield lK, Johnson RP, Kilcoyne RF The hgaments of the wnst and theIr functIOnal slgOificance Anat Rec 1976,186417